bluuebunny/crossref_metadata_2025 huggingface dataset:
The response of leaves to heat stress in tomato plants with source-sink modulated by growth regulators
Authors: Starck Zofia , Witek-Czcpryńska Barbara , Blancard Dorota
Published: April 2013

The response to heat stress was investigated in heat-sensitive, Roma V. F. and heat-tolerant, Robin, cultivars whose fruit growth was stimulated by NOA + GA3 , or NOA + GA3 + zeatin. The treated plants were compared with untreated control plant. In each of these series half of the plants were subjected to one or three cycles of heat stress. A single cycle of 38°/25°C day and night did not significantly affect either the respiration rate or chlorophyll content. In PGR-untreated intact cv. Roma, heat stress inhibited starch formation during the day and strongly depressed night export from the blades. High temperature depressed the night transport less in plants having a higher sink demand of fruits in plant treated with PGR. In this case the amount of substances available for export was much higher and both sugars and starch were more intensively remobilized at night. In intact Robin plants, PGR and heat stress much less affected sugar and starch content. High temperature diminished noctural starch remobilization only in the NOA + GA3 series. Leaf disc growth was evaluated as a measure of response to heat stress after elimination of the direct effect of fruit demands. One cycle of high temperature did not negatively affect the growth of leaf discs; it even caused thermal low growth activation in both cultivars. Three cycles of heat stress depressed leaf disc growth after short-term stimulation, especially in Roma plants. Immediately after 3-day heat stress, there was no response of discs to GA3 or zeatin added to the solution on which the discs were floated. Leaf disc growth of Robin control and NOA + GA3 series was very similar in plants from optimal temperature conditions. High temperature inhibited only disc growth of the NOA + GA3 series owing to depression of starch break-down, diminishing the pool of sugars. In contrast, leaf discs of Roma cv. excided from NOA + GA3 treated plants from the optimal temperature series, grew more intensively as compared with control plants, owing to a higher content of sugar available for growth.
Lichens from the Admiralty Bay region, King George Island (South Shetland Islands, Antarctica)
Authors: Olech Maria
Published: April 2013

61 Species new to the Admiralty Bay region are reported. Among them 51 are new to King George Island, 35 to the South Shetland archipelago, 15 to the Antarctic zone, and 6 to the Southern Hemisphere. A further 49 species were found at new localities.
The structures of four triterpenoid saponins isolated from the seed of Trifolium incarnatum
Authors: Jurzysta Marian , Price Keith , Ridout Caralyn , Fenwick Roger
Published: April 2013

A novel bisdesmosidic saponin, 3-0-[α-L-rhamnopyranosyl(1 - 2)-β-D-galactopyranosyl (1-2)-β-D-glucuronopyranosyl]-22-O-[β-D-glucopyranosyl(1-2)-β-D-glucopyranosyl] ole­an-l2-ene-24-ol has been isolated from the seed of the clover, Trifolium incarnatum. The structure of this and of three other structurally related saponins, 3-0-(β-D-glucuronopyra-nosyl)olean-l2-ene-22, 24-diol, soyasaponin I and soyasaponin III have been assigned on the basis of spectral and chemical evidence.
The Impact of Challenging Geometry and Measurement Units on the Achievement of Grade 2 Students
Authors: Gavin M. Katherine , Casa Tutita M. , Adelson Jill L. , Firmender Janine M.
Published: April 2013

The primary goal of Project M2was to develop and field–test challenging geometry and measurement units for all K—2 students. This article reports on the achievement results for students in Grade 2 at 12 urban and suburban sites in 4 states using the Iowa Tests of Basic Skills (ITBS) mathematics concepts subtest and an open–response assessment. Hierarchical linear modeling indicated no significant differences between the experimental (n = 193) and comparison group (n = 192) on the ITBS (84% of items focused on number); thus, mathematics concepts were not negatively impacted by this 12–week study of geometry and measurement. Statistically significant differences (p < .001) with a large effect size (d = 0.89) favored the experimental group on the open–response assessment. Thus, the experimental group exhibited a deeper understanding of geometry and measurement concepts as measured by the open–response assessment while still performing as well on a traditional measure covering all mathematics content.
Glycerolysis of Crude Methyl Esters with Crude Glycerol from Biodiesel Production
Authors: Echeverri David A. , Cardeño Fernando , Rios Luis A.
Published: April 2013

Glycerolysis of crude fatty acid methyl esters (FAME) with crude glycerol derived from biodiesel production was performed. The reaction was accomplished at temperatures ranging between 160 and 200 °C and molar ratios of FAME to glycerol ranging between 1.5 and 3.0. Increasing the temperature improved the formation rate of monoglycerides (MG) and diglycerides (DG). However, increasing both the temperature and the molar ratio of glycerol to FAME diminished the formation of MG. Best results (43 % MG and 26 % DG in 10 min) were obtained at 200 °C using the lowest concentration of glycerol. The effects of soap and NaOH present in crude glycerol were controlled by carrying out the reaction with pure glycerol. In comparison with NaOH‐catalyzed reactions, soap‐catalyzed reactions resulted in a slower formation rate of products. However, soap‐catalyzed reactions were less prone to secondary reactions, affording maximum yields of MG and DG, which were higher than those obtained with NaOH‐catalyzed reactions at 180 and 200 °C.
Draft Genome Sequences of Five Yersinia pseudotuberculosis ST19 Isolates and One Isolate Variant
Authors: Platonov Mikhail E. , Blouin Yann , Evseeva Vera V. , Afanas'ev Maxim V. , Pourcel Christine , Balakhonov Sergey V. , Vergnaud Gilles , Anisimov Andrey P.
Published: April 2013

We report the first draft genome sequences of five
Yersinia pseudotuberculosis
isolates of sequence type (ST) 19 and of a variant from one of the five isolates. The total length of assemblies ranged from 4,226,485 bp to 4,274,148 bp, including between 3,808 and 3,843 predicted coding sequences.
Growth Mode for Carbon Micro Coils having Double Helix Geometries
Authors: Park Semi , Jeon Youn-Chul , Kim Sung-Hoon
Published: April 2013

Formation of carbon coils were investigated according to the injection starting stage of an incorporated additive gas (SF6) flow during the overall reaction. Among the different injection stage of SF6 flow, the initial stage is most effective for the formation of the microsized carbon coils. The formation of carbon coils was also investigated step by step during the reaction. In an early step of the reaction, merely carbon nanofilaments could be observed on the sample. With increasing the reaction time, the formation of the carbon coils was initiated and their densities increased. The double helix geometry of the microsized carbon coils seemed to be developed by the precipitating carbon elements from the spinning catalyst. Based on the close investigating results of the coil head area, the detailed growth mode for the double helix geometry of the microsized carbon coils was proposed and discussed.
(Invited) Micro-to-Nanostructures to Probe Electrocatalysts by SERS
Authors: Yagi Ichizo , Inokuma Kiyoshi , Ohta Narumi
Published: April 2013

Focusing the void plasmon toward the rim part of the sphere segment void (SSV) type plasmonic crystalline structures are further developed by retaining the polystyrene nanospheres inside the voids. Plasmonic whispering gallery modes (WGMs) are proved to appear in such the hybrid structures by the measurements of reflectance spectroscopy and cause the improvement of signal/background ratio in the SERS spectra. From the detailed experimental analyses, a possibility of the plasmonic WGMs to enhance the molecular signal at the Pt electrode surfaces is shown.
Hierarchically ZnO Nano Crystalline Aggregates Synthesized Through an Inter-Phase Precipitation Method and Application in Dye-Sensitized Solar Cells
Authors: Gao Rui , Wang Liduo , Zhang Qifeng , Cao Guozhong
Published: April 2013

A novel interface precipitation method has been developed to synthesize hierarchically structured ZnO nanocrystallite aggregates. Such synthesized ZnO nanocrystallite aggregates demonstrated as promising structure for high power conversion efficiency when used as photoelectrode in dye-sensitized solar cells (DSCs). It has large specific surface area, efficient dye-loading and effective light scattering within the photoelectrode. Such structured ZnO film annealed at different temperature was analyzed and a power conversion efficiency of 5.07% has been obtained with annealed at 300 oC.
Metal Nanoparticle Aerogels and Their Applications
Authors: Herrmann Anne-Kristin , Liu Wei , Gaponik Nikolai , Bigall Nadja-Carola , Eychmüller Alexander
Published: April 2013

Gels and aerogels manufactured from a variety of metal nanoparticles available in colloidal solutions have recently proven to provide an opportunity to marry the nanoscale world with that of materials of macro dimensions which can be easily manipulated and processed, whilst maintaining most of the nanoscale properties. The materials carry an enormous potential for applications. This is largely related to their extremely low density and high porosity providing access to the capacious inner surface of the interconnected nanoobjects they consist of. In addition we prove the electrocatalytical activity of freestanding cyclodextrin modified palladium nanoparticle aerogels towards the oxidation of ethanol with extremely high electrocatalytic current density and good durability.
Nanostructured Composite Electrode based on Hydrous Manganese Oxide and Mesoporous Carbon for Electrochemical Supercapacitor: Synthesis, Morphology and Electrochemical Characterization
Authors: Ha The An , Le Phung My Loan , Nguyen T.P. Thoa , Tran Van Man
Published: April 2013

MnO2/C composites electrodes are synthesized by two different methods: chemical reduction and electrochemical deposition. The morphology and structure of samples are examined by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy. Electrochemical properties are characterized by cyclic voltammetry (CV) in aqueous 2M NaCl. -MnO2 structure were obtained for all samples. In chemical reduction, the carbon addition improves specific capacitance (SP) as well as the specific surface area (SSA). The highest value was reached at 30% carbon content. The effect of carbon nature was also studied, such as C black, C super P and C Vulcan XC-72R. The electrochemical deposition of MnO2 was investigated on graphite substrate (EMD) and modified graphite substrate (EMD-2L) by two layers of hydrophobic and hydrophilic. The electrodes exhibited the good cyclic performance (< 5% capacity loss after 300 cyles) and good specific capacitance (375 F.g-1 as to 240 F.g-1 at 1 mV.s-1)
Study of H, O and C Adatoms Surface Diffusion on Graphene by Computer Simulation
Authors: Gorbenko Vitaliy Ivanovich
Published: April 2013

The ab initio methods of GAMESS package have been used to calculate the adsorption and the surface diffusion properties of H, O and C adatoms on graphene sheet. The graphene sheet was presented by cluster model with hydrogen atoms on perimeter. The potential-energy profiles of interaction of the adatoms with graphene have been obtained. The essential difference of the profiles and the energy barriers has been found for all adsorbate species.
Impact of the Various Catalysts (Pt, Pt-Ru) Deposited onto Carbon Support to the Slow Oxygen Reduction Reaction Kinetics
Authors: Härk Eneli , Sepp Silver , Valk Peeter , Vaarmets Kersti , Nerut Jaak , Jäger Rutha , Lust Enn
Published: April 2013

Micro- and mesoporous carbide derived carbons synthesized from molybdenum and tungsten carbide were used as supports for platinum and Pt-Ru alloy catalysts. The scanning electron microscopy, X-ray diffraction, Raman spectroscopy, high resolution transmission electron microscopy and low temperature N2 adsorption experiments were carried out to characterize the structure of prepared materials. The kinetics of oxygen reduction was studied using cyclic voltammetry and rotating disc electrode in 0.5 M H2SO4 solution. The synthesized materials exhibited high specific surface area. The platinum or Pt-Ru alloy deposited onto the surface of carbon in the form of nanoparticles or agglomerates of nanoparticles. All catalysts showed high activity towards oxygen reduction.
Towards Understanding the Essential Role Played by the Platinum-Support Interaction on Electrocatalytic Activity
Authors: Ma Jiwei , Habrioux Aurelien , Gago Aldo , Alonso-Vante Nicolas
Published: April 2013

Different substrates supported Pt-based electrocatalysts via carbonyl route and photo-deposition method were synthesized. These methods are responsible for the heterogeneous nucleation of platinum nanoparticles onto the substrate. Evidences of strong interaction between the metal and substrate are clearly brought into light from CO stripping experiments. The obtained results can be attributed to the catalytic mediation of the oxide under UV-irradiation to generate a Pt-M nanoalloy. The nature of the interaction appears to be induced by the nucleation type of particles onto the substrate. The substrate effect is responsible for modifying the stability of the catalysts, their electronic properties and consequently their catalytic activity towards the oxygen reduction reaction (ORR) and CO electro-oxidation.
Synthesis of RuxIr1-xO2 Anode Electrocatalysts for Proton Exchange Membrane Water Electrolysis
Authors: Audichon Thomas , Mamaca Nurcan , Morais Claudia , Servat Karine , Napporn Teko W. , Mayousse Eric , Guillet Nicolas , Kokoh K. Boniface
Published: April 2013

Ru and Ir based materials were prepared by the thermal decomposition of polymeric precursor's method. The anode catalysts free from carbon substrate were obtained by tailoring the reaction process to avoid occurrence of CO2 formation during water electrolysis. Various Ir contents were added in the Ru catalytic compositions for improving the oxidation-resistance of RuO2 which was the best metallic oxide in H2O splitting. Their physical characterizations revealed the presence of agglomerates due probably to the heat treatment process consisting in the removal of organic carbon at 400 ºC. The prevalent existence of RuO2 and IrO2 in the anode materials was confirmed by XPS experiments and the electrochemical measurements enabled to show that RuxIr1-xO2 materials were more active towards water oxidation than IrO2 catalyst. The O2 evolution process started at 1.45 V with Ru0.9Ir0.1O2 in the anodic compartment of a 25 cm2 Proton Exchange Membrane Water Electrolyzer at 60ºC.
Synthesis and Characterization of New Non-Platinum Electrocatalysts for Oxygen Reduction
Authors: Dembinska Beata , Dobrzeniecka Anna , Glowienka Malgorzata , Stroka Jadwiga , Kulesza Pawel J.
Published: April 2013

A new group of carbon-supported ruthenium- and iridium-based electrocatalysts for oxygen reduction reaction (ORR) was synthesized, using RuCl3 or IrCl3 and selenourea (as precursor of both Se and N). The heat treated catalysts (later abbreviated as RuSeN/C and IrSeN/C) were subjected to physical characterization, like X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Studies revealed changes in surface properties of Ru- and Ir- based catalysts. Catalytic performances of obtained catalysts were evaluated using Rotating Ring Disk Electrode (RRDE) in acid solution. The ORR activity and hydrogen peroxide generation on designed selenides were dependent on the ratio of metal and selenourea used in precursor blend and were separately characteristic for ruthenium and iridium. While RuSeN/C exhibited high ethanol tolerance, the ORR activity of IrSeN/C in the presence of ethanol depended on the amount of selenourea. CoSeN/C and FeSeN/C were also prepared and characterized as low-cost alternative catalysts.
Processing, Activity and Microstructure of Oxygen Evolution Anodes Prepared by a Dry and Direct Deposition Technique
Authors: Roller Justin M , Arellano-Jiménez Josefina , Jain Rishabh , Yu Haoran , Maric Radenka , Carter C. B.
Published: April 2013

Thin films of RuxIr1-xO2-y have been deposited by a dry combustion process directly onto polypropylene and quartz coupons for characterization and on a gold disk to evaluate the electrochemical suitability as an oxygen evolution electrode. Compositional analysis on the oxygen evolution catalyst suggests a chemical formula of Ru0.41Ir0.59O2-y. Bulk diffraction of the thin film Ru0.41Ir0.59O2-y suggests phases of IrO2 and RuO2 and to a lesser extent Ru metal with no Ir metal. The photoelectron emission spectrum of the film suggests that Ru exists primarily in the oxidized state. The integrated area of the Ir metal peaks is an order of magnitude larger than the RuO2 peaks and 6 times larger than the corresponding oxide suggesting a surface enriched in Ir metal in contrast to the diffraction findings. An exceptional oxygen evolution current of 25-40 mA/cm2 was observed for a Ru0.41Ir0.59O2-y thin film supported on a gold rotating disk electrode in a 0.5 M H2SO4 electrolyte measured at a potential of 1.6 V. The corresponding mass activity of the electrode is exceptionally high at 400 mA/mg of Ru0.5Ir0.5O2 compared to 50-75 mA/mg of Ru0.5Ir0.5O2 from the literature.
Economic Operational Planning of Grid-connected Battery Energy Storage
Authors: Fares Robert L. , Meyers Jeremy P.
Published: April 2013

In this paper, we develop a framework for valuing a battery energy storage system as it participates in the wholesale electricity market. We utilize an economic optimization routine with an internal battery energy storage model to plan when a battery should offer its power into the marketplace to maximize its benefit to the electric grid-and maximize its value. We examine the potential value of a vanadium redox flow battery (VRFB) used for frequency regulation service in the Texas organized electricity market from 2007-2009. Our results show that the price point where a VRFB system used for frequency regulation in Texas would be a good investment is approximately $1500/kW. We show that the expected annual revenue from frequency regulation is highly dependent on variations in wholesale prices, and that longer-duration storage could provide increased revenue from frequency regulation up to approximately 3 hours of storage capacity.
Performance Evaluation of Microporous Separator in Fe/V Redox Flow Battery
Authors: Wei Xiaoliang , Luo Qingtao , Li Bin , Nie Zimin , Miller Eric , Chambers Jeff , Sprenkle Vincent L , Wang Wei
Published: April 2013

The newly developed Fe/V redox flow battery has demonstrated attractive cell performance. However, the deliverable energy density is relatively low. To compete with other redox flow battery systems, cost reduction of the Fe/V system is necessary. This paper describes evaluation of hydrocarbon-based Daramic microporous separators for use in the Fe/V system. Separator B having ion exchange capacity demonstrated excellent capacity retention capability, which exhibited energy efficiency above 65% over a broad temperature range of 5-50oC and at current densities up to 80mA∙cm-2. Therefore, this separator shows great potential to replace the highly expensive Nafion membrane. This will drive down the capital cost making the Fe/V system a more promising low-cost energy storage option.
Validation of algorithms for delamination detection in composite structures using experimental data
Authors: Ihesiulor Obinna K , Shankar Krishna , Zhang Zhifang , Ray Tapabrata
Published: April 2013

This research work deals with aspects concerned with delamination detection in composite structures as revealed by an approach based on vibration measurements. Variations in vibration characteristics generated in composite laminates indicate the existence of delaminations because degradation due to delamination causes reduction in flexural stiffness and strength of the material and as a result vibration parameters like natural frequency responses are changed. Hence, it is possible to monitor the variation in natural frequencies to identify the presence of delamination, and assess its size and location for online structural health monitoring (SHM). The approach to this paper, therefore, typically depends on undertaking the analysis of structural models implemented by finite element analysis (FEA). The numerical solutions using FE models known as the simulator computes the natural frequencies for the delaminated and undelaminated specimens of composite laminates. However, these FE models are computationally expensive, and surrogate (approximation) models are introduced to curtail the computational expense. The simulator is employed to solve the inverse problem using algorithms based on computational intelligence concepts. An artificial neural network (ANN) model is developed to also solve the inverse problem for delamination detection directly and to provide surrogate models integrated with optimization algorithms (the gradient-based local search and non-dominated sorting genetic algorithm-II) to contain the computationally expensive simulations by FEA. This approach is termed as surrogate assisted optimization and it is seen that the engagement of surrogate models in lieu of the FE models in the optimization loop greatly enhances the accuracy of delamination detection results within an affordable computational cost and provides control over handling different variables. Meanwhile, to aid with the building of effective surrogate models using substantial number of training datasets, K-means clustering algorithm is harnessed and this effectively reduces the large training datasets usually required for ANN training. This paper demonstrated that ANN and optimization algorithms with surrogates show immense potentialities for use in delamination damage detection scenarios. Prediction errors of the algorithms were quantified and they were shown to be satisfactory when applied to previously experimental data. The algorithms in their inverse formulations are capable of predicting accurately delamination parameters. Hence, these algorithms should be employed for application in the domain of SHM where their small computational requirements could be exploited for online damage detection.
Fatigue and impact response of gel-coated glass mats/polyester composites
Authors: Capela C , Ferreira JM , Cravo H , Costa JM
Published: April 2013

Composites based on polyester matrices reinforced with fiber glass mats are widely used in the automotive industry, incorporating in many cases a gel coat surface layer. This paper presents the results of a current study in polyester/short fiber glass mat composites processed by hand lay-up moulding. Different lay-up architectures were tested under impact and fatigue bending loadings. Furthermore, the influence of the gel coat surface layer on fatigue and impact loading performances was also analysed. The composites tested with gel coat layer under compression loading exhibit significant higher bending stiffness, static and fatigue strength than when the gel coat layer was under tensile loading. The impact response showed a slight variation of the peak load and on the elastic recuperation and a significant increase on maximum displacement and absorbed energy with the increase of the incident impact energy. Both energy recovery, in percentage of the incident impact energy, and residual bending strength showed a marked and almost linear decreasing with the increase of the impact energy for all loading conditions, while the absorbed energy increased with the incident impact energy, reaching about 80% of impact energy for the highest impact energies
Paradoxical Inequalities
Authors: Milner Murray
Published: April 2013

Peer relationships in secondary schools in two different cultural areas of India are compared. A general theory of status relations and a specification of the distinctive cultural features of each area are used to explain the observed differences in peer inequality, clique formation, petty deviance, putdowns, fashion consciousness, romantic relationships, and gossip. A surprising finding is that the degree of status inequality among school peers is inversely related to an ideological emphasis on equality and hierarchy: The more egalitarian the cultural ideology, the greater the inequality in peer relationships, and conversely, the more emphasis on hierarchy, the less the actual peer inequality. The apparent paradox is resolved by specifying the structural mechanisms through which cultural and ideological differences operate. Brief comparisons with the United States suggest that these findings are not unique to India.
War: Fighting the Enemies of God, not Man
Authors: Pierce Madison N.
Published: April 2013

The role of warfare in the life of the Christian is a debated topic. Typically, one wonders if the Christian can participate in warfare, but perhaps the question is more appropriately should the Christian do so? In this article I hope to demonstrate the role of conflict in the Bible and two distinctions: the difference between God as warrior and humans as warriors, and the difference between God's enemies and human enemies. For instance, God is presented positively as a warrior, but human warfare is condoned only if God sanctions it. God's enemies are those opposed to God's purpose, whereas human conflicts are often fought according to human purposes. Warfare is traced through Scripture, and several hermeneutical approaches to warfare are discussed and evaluated. It appears that God's overall conflict with Satan and evil should be the basis for any conflict—especially conflict undertaken in the name of God.
How Do Alcohol and Relationship Type Affect Women’s Risk Judgment of Partners With Differing Risk Histories?
Authors: Norris Jeanette , Kiekel Preston A. , Morrison Diane M. , Davis Kelly Cue , George William H. , Zawacki Tina , Abdallah Devon Alisa , Jacques-Tiura Angela J. , Stappenbeck Cynthia A.
Published: April 2013

Understanding how women judge male partners’ sexual risk is important to developing risk reduction programs. Applying a cognitive mediation model of sexual decision making, our study investigated effects of alcohol consumption (control, low dose, high dose) and relationship type (disrupted vs. new) on women’s risk judgments of a male sexual partner in three sexual risk conditions (low, unknown, and high). After random assignment to an experimental condition, 328 participants projected themselves into a story depicting a sexual interaction. The story was paused to assess primary appraisals of sexual and relationship potential and secondary appraisals of pleasure, health, and relationship concerns, followed by sexual risk judgments. In all risk conditions, alcohol and disrupted relationship increased sexual potential, whereas disrupted relationship increased relationship potential in the low- and high-risk conditions. In the unknown-risk condition, women in the no-alcohol, new relationship condition had the lowest primary sexual appraisals. In all conditions, sexual appraisals predicted all secondary appraisals, but primary relationship appraisals predicted only secondary relationship appraisals. Secondary health appraisals led to increased risk judgments, whereas relationship appraisals predicted lower risk judgments. Possible intervention points include helping women to re-evaluate their safety beliefs about past partners as well as to develop behavioral strategies for decreasing hazardous drinking.
Autonomous task partitioning in robot foraging: an approach based on cost estimation
Authors: Pini Giovanni , Brutschy Arne , Pinciroli Carlo , Dorigo Marco , Birattari Mauro
Published: April 2013

We propose an approach for autonomous task partitioning in swarms of foraging robots. Task partitioning is the process of decomposing tasks into sub-tasks. Task partitioning impacts tasks execution and associated costs. Our approach is characterized by the use of a cost function, mapping the size of sub-tasks to the overall task cost. The robots model the cost function and use the model to select sub-tasks to perform, aiming to minimize costs. Our approach separates the task partitioning process from task-specific actions and it does not require a priori assumptions to be made about the best partitioning strategy to employ. We study a foraging scenario in which object transportation is performed by different robots, each moving objects for a limited distance. The robots autonomously decide the distance traveled on the basis of our approach. The robots use odometry for navigational purposes; we show that task partitioning reduces the impact of odometry errors and improves performance. We validate our approach using simulation-based experiments. We study how the swarm partitions transportation under a number of experimental conditions characterized by different levels of odometry accuracy, size of the environment and the swarm, and total transportation distance. Our approach leads to partitioning solutions that are appropriate for each condition.
The Discursive Manifestation of Past and Present Through the Spatial Organization of the Ashura Procession
Authors: Nejad Reza Masoudi
Published: April 2013

This article investigates the spatial organization of the Shi’i-Muslim procession and its changes under the Iranian modernization in the city of Dezfoul. The study is the result of interdisciplinary research integrating spatial analyses and qualitative fieldwork to explore the procession as a social and spatial phenomenon. The analyses show the ritual has not been unilaterally affected by transformations of urban shape and also by social transformations. This article argues that the ritual organization will be stable as long as social organization is not fundamentally changed, even when the city shape/morphology undergoes major change. The analyses show that the processions were locally organized in each part of the city because of the traditional Heidari-Nemati division. The processions were reorganized in the 1950s to ritualize social integration in Dezfoul, while at the same time the idea of traditional social division was kept alive through the reorganized processions. The new procession routes through the transformed city also preserve the idea of the traditional city structure. The article concludes by proposing that the processions, as a lived environment, constitute a space in which past and present coexist in a discursive relationship.
Risk of multiple sclerosis after a first demyelinating syndrome in an Australian Paediatric cohort: clinical, radiological features and application of the McDonald 2010 MRI criteria
Authors: Tantsis Esther M , Prelog Kristina , Brilot Fabienne , Dale Russell C
Published: April 2013

Background:

The risk of multiple sclerosis (MS) is dependent on multiple variables, including geographical location. There is increasing interest in the early recognition and treatment of MS in children.

Method:

Using univariate and multivariate analysis, we determined the clinical and radiological features that were predictive of MS in 88 children from New South Wales, Australia, with a first acute demyelinating syndrome (ADS) who were followed for a minimum of one year. We tested the McDonald, KIDMUS, Callen and Verhey MRI criteria for paediatric MS.

Results:

After a mean follow-up of 5.2 years, 13/88 (15%) of children had MS. Using multivariate analysis, preceding infection was protective of MS, and corpus callosal lesions, the combined presence of both well and poorly demarcated lesions, and contrast-enhancing lesions on MRI were predictive of MS. The sensitivity and specificity of the respective radiological criteria were McDonald 2005 (69%, 68%), McDonald 2010 (58%, 95%), KIDMUS (8%, 100%), Callen (69%, 85%) and Verhey (62%, 84%). When McDonald 2010 criteria were applied to baseline and serial scans, the sensitivity and specificity was 91% and 93%.

Conclusion:

Despite the long follow-up, the risk of MS appears lower in New South Wales children compared to previously reported cohorts. Radiological features are more predictive than clinical features in predicting MS. The McDonald 2010 criteria performed well although the dissemination in time criteria on baseline scans is difficult to apply to children with encephalopathy.
Evaluating the antibacterial properties of chitosan fibres embedded with copper ions for wound dressing applications
Authors: Barnabas John , Miraftab Mohsen , Qinand Yimin , Changjun Zhu
Published: April 2013

Chitosan is a natural polymer that is well known for its inherent antimicrobial ability and natural healing properties and hence it has been developed into fibres that are used for wound dressing applications. To increase its antimicrobial potency, these fibres are treated with copper sulphate. In a wound environment, copper ions have potent antimicrobial abilities due to their propensity to bind with proteins and ability to produce hydrogen peroxides. In this article, copper-treated chitosan fibres of different concentrations have been tested and analysed to determine the most effective antimicrobial dose for potential wound care dressings. Selected common skin microflora, i.e. Staphylococcus aureus, Staphylococcus epidermidis and Micrococcus luteus, have been used to test the chitosan–copper combinations. The analysis, based on the test methods of zone of inhibition, spectrophotometry and plating technique, has shown that copper concentration of 0.3 gm/ml was highly effective against the three bacteria and could potentially be most suitable formulation for wound dressing applications.
Factors affecting the motivation of healthcare professionals providing care to Emiratis with type 2 diabetes
Authors: Alhyas Layla , Nielsen Jessica D Jones , Dawoud Dalia , Majeed Azeem
Published: April 2013

Objective

We aimed to identify facilitators of and barriers to healthcare professionals’ motivation in a diabetes centre in the United Arab Emirates (UAE).

Design

A qualitative research approach was employed using semistructured interviews to assess perception of and attitudes regarding healthcare professionals’ motivation in providing good quality diabetes care.

Setting

A diabetes centre located in Abu-Dhabi, UAE.

Participants

Healthcare professionals including specialist physicians, dieticians, podiatrists, health educators and nurses were recruited through purposive sampling.

Main outcome measures

After data collection, the audiotaped interviews were transcribed verbatim and subjected to content analysis.

Results

Nine semistructured interviews were conducted with healthcare professionals of various professional backgrounds. Important facilitators and barriers related to patient, professional, organization and cultural factors were identified. Barriers that related to heavy workload, disjointed care, lack of patient compliance and awareness, and cultural beliefs and attitudes about diabetes were common. Key facilitators included the patient's role in achieving therapeutic outcomes as well as compliance, cooperation and communication.

Conclusion

This qualitative study provides some unique insights about factors affecting healthcare professionals’ motivation in providing good quality care. To improve the motivation of healthcare professionals in the management of diabetes and therefore the quality of diabetes care, several steps are needed. Importantly, the role of primary care should be reinforced and strengthened regarding the management of type 2 diabetes mellitus, privacy of the consultation time should be highly protected and regulated, and awareness of the Emirate culture and its impact on health should be disseminated to the healthcare professionals providing care to Emirates with diabetes. Also, greater emphasis should be placed on educating Emiratis with diabetes on, and involving them in, the management of their condition.
The psychological impact of torture
Authors: de C Williams Amanda C , van der Merwe Jannie
Published: April 2013

Many refugees in the developed world are survivors of torture and present with health needs without their traumatic experience being disclosed or identified. Chronic pain is a common problem, as are symptoms of post-traumatic stress disorder (PTSD), anxiety, depression, and other distress. Current circumstances, particularly poverty, uncertainty about asylum, separation from or loss of family and roles, and difficulties settling in the host country, all contribute to current psychological problems and exacerbate existing ones. Psychological treatment studies tend to be focused either on PTSD diagnosis and use protocol-driven treatment, usually in the developed world, or on multiple problems using multimodal treatment including advocacy and welfare interventions, usually in the developing world. Reviews of both of these, and some of the major criticisms, are described. Psychological interventions tend to produce medium-sized changes in targeted measures of distress, when compared with waiting lists or standard treatment, but these may fall well short of enabling recovery, and long-term follow-up is rare. A human rights context, with reference to cultural difference in expressing distress and seeking help, and with reference to the personal meaning of torture, is essential as a basis for formulating treatment initiatives based on the evidence reviewed.

Summary points

Refugees with a history of torture may have a wide range of psychological and social difficulties which do not easily fit within diagnostic categories. Torture and its sequelae can have multiple meanings and, in the clinical context, it is the interpretation of the torture survivor that matters. There are doubts about applying the concept and measures of post-traumatic stress disorder: symptoms should be assessed separately. Current circumstances can be as important as trauma history in understanding the psychological state of a torture survivor. Cognitive behavioural therapy and narrative exposure therapy seem equally effective in reducing trauma symptoms, and to a lesser extent, depression.
Halting the spread of epidemic Pseudomonas aeruginosa in an adult cystic fibrosis centre: a prospective cohort study
Authors: Ashish Abdul , Shaw Matthew , Winstanley Craig , Humphreys Linda , Walshaw Martin J
Published: April 2013

Summary

Objectives

To assess if cohort segregation policies are effective in preventing cross-infection in cystic fibrosis (CF) clinics.

Design

A prospective cohort study.

Setting

A large adult CF centre in Northwest England.

Participants

All CF patients cared for at the Liverpool adult CF centre 2003–2009.

Methods

Regular sputum sampling with genotyping of Pseudomonas aeruginosa (Psa) isolates led to a policy of inpatient and outpatient segregation by microbiological group.

Main outcome measures

Prevalence and cross-infection/super-infection rates of a transmissible Psa strain, i.e. the Liverpool epidemic strain (LES) in adult CF patients at the Liverpool adult CF centre from 2003 to 2009.

Results

There was a decline in the proportion of patients with LES (71–53%) and an increase in those with unique strains (23–31%) and without Psa infection (6–17%) from 2003 to 2009. There were two cases of LES super-infection and one case of new chronic Psa infection (with a unique strain). There were no cases of transmissible strain infection in patients previously uninfected by Psa.

Conclusions

Our segregation policy has halted the spread of the commonest highly transmissible strain in the UK (LES) in our clinic, without endangering patients who were not previously infected with Psa. It confirms that if genotypic surveillance is used, it is unnecessary to segregate patients infected with unique strains from those without Psa infection.
High-Power Ho:YAG Laser in-band Pumped by Laser Diodes at 1.9 μm and Wavelength-Stabilized by a Volume Bragg Grating
Authors: Lamrini S. , Koopmann P. , Scholle K. , Fuhrberg P. , Hofmann M.
Published: April 2013

The first high-power Ho:YAG laser wavelength-stabilized by a volume Bragg grating is reported. A maximum output power of 15 W and a slope-efficiency of 37 % were achieved using in-band diode pumping. The spectrum of the Ho:YAG laser showed a stable narrow bandwidth operation. In free-running operation a maximum output power of 46 W and a slope efficiency of 62 % were achieved. The emitted wavelength of the free-running laser was 2118 nm and 2096 nm in wavelength-stabilized operation. In free-running Q-switched operation the maximum output pulse energy at a repetition rate of 250 Hz was 6.2 mJ, limited only to avoid damage of the optical surfaces.
Relation between group delay and energy storage in dispersive dielectric mirror coatings
Authors: Antal Peter Gyula , Szipocs Robert
Published: April 2013

We show that the reflection group delay of a highly reflective, dielectric multilayer mirror is proportional to the energy stored by the standing wave electromagnetic field built up in such 1D photonic bandgap (PBG) structures.
Fiber amplified Q-switched ns-sources spectrally combined by the use of interference filters
Authors: Schmidt O. , Wirth C. , Nodop D. , Limpert J. , Schreiber T. , Eberhardt R. , Tünnermann A.
Published: April 2013

We report on a simple scheme to spectrally combine four ns-pulsed sources using three off-the-shelf dielectric interference filters as combining elements. 208 W of average power and 6.3 mJ of pulse energy are obtained at two different repetition frequencies.
Ultrabroad continuous-wave tuning of ceramic Cr:ZnSe and Cr:ZnS lasers
Authors: Sorokin E. , Sorokina I. T. , Mirov M.S. , Fedorov V.V. , Moskalev I.S. , Mirov S.B.
Published: April 2013

Using a single set of optics, we demonstrate ultrabroad tuning over more than 1300 nm from 1973 to 3349 nm in Cr:ZnSe and from 1962 to 3195 nm in Cr:ZnS at <10 GHz linewidth.
Efficient Mode-Locked Yb:Lu2O3 Thin Disk Laser with an Average Power of 103 W
Authors: Baer C. R. E. , Kränkel C. , Saraceno C. J. , Heckl O. H. , Golling M. , Südmeyer T. , Keller U. , Peters R. , Petermann K. , Huber G.
Published: April 2013

We demonstrate power scaling of an Yb:Lu2O3 thin-disk laser to an average power of 103 W setting a new record for mode-locked laser oscillators. The laser generates 885-fs pulses with an optical-to-optical efficiency of 42%.
Compression of mJ-scale chirped-amplified pulses to sub-20 fs using high-dispersive mirrors
Authors: Ahmad Izhar , Pervak Vladimir , Trushin Sergei , Major Zsuzsanna , Karsch Stefan , Krausz Ferenc
Published: April 2013

We presented the development of an all-dispersive-mirror compressor for sub-TW CPA systems. The compression of 4.8-ps 1.4-mJ amplified stretched pulses to 19.1 fs is demonstrated, using 52 reflections on high-dispersive mirrors with ~90% throughput.
0.4 µJ, Sub-10-fs Pulses from a MHz-NOPA
Authors: Emons Moritz , Steinmann Andy , Binhammer Thomas , Palmer Guido , Morgner Uwe
Published: April 2013

We present a non-collinear optical parametric amplifier (NOPA) delivering sub-10-fs pulses with 420 nJ of pulse energy. The system is driven by pulse trains at 1-MHz repetition rate from an amplified Yb:KYW oscillator with cavity-dumping.
Novel ultra broadband front-end system for Vulcan 10 PW OPCPA project
Authors: Tang Y. , Lyachev A. , Hernandez-Gomez C. , Musgrave I. , Ross I. N. , Chekhlov O. , Matousek P. , Collier J.
Published: April 2013

We report the recent progress in the development of a novel broadband front-end system, capable of producing sub-30fs pulses centered at ~910nm with 0.4J pulse energy at 2Hz for the Vulcan 10 PW OPCPA project.
High-Resolution Spatio-Spectral Characterization of Noncollinear Optical Parametric Amplifiers
Authors: Bromage J. , Dorrer C. , Zuegel J. D.
Published: April 2013

A MHz-repetition-rate noncollinear optical parametric amplifier is characterized using spatially resolved spectral interferometry. High-resolution images of the frequency-dependent amplitude and phase reveal high-order spatio-spectral coupling, corresponding to spatiotemporal Strehl values as large as 0.86.
Single-Walled Carbon Nanotube Saturable Absorber Mode-Locking of a Tm:KLuW Laser Near 2 µm
Authors: Cho Won Bae , Yim Jong Hyuk , Choi Sun Young , Lee Soonil , Rotermund Fabian , Schmidt Andreas , Petrov Valentin , Steinmeyer Günter , Griebner Uwe , Mateos Xavier , Pujol Maria C. , Carvajal Joan J. , Aguilo Magdalena , Diaz Francesc
Published: April 2013

Stable and self-starting mode-locking of a Tm:KLu(WO4)2 laser using a single-walled carbon nanotubes based saturable absorber is demonstrated generating ~10-ps pulses at 1.94 µm with powers up to 220 mW at 126 MHz.
Diode-pumped passively Q-switched Tm:KLuW laser with a Cr2+:ZnSe saturable absorber
Authors: Segura Martha , Mateos Xavier , Pujol Maria Cinta , Carvajal Joan Josep , Aguiló Magdalena , Díaz Francesc , Panyutin Vladimir , Griebner Uwe , Petrov Valentin
Published: April 2013

A passively Q-switched Tm:KLuW laser using Cr2+:ZnSe as saturable absorber delivered pulse energies as high as 16 µJ at a repetition rate of 6.5 kHz around 2 µm.
Low-threshold and highly efficient Gd3+, Lu3+ co-doped KY(WO4)2: Yb3+ planar waveguide lasers
Authors: Geskus D. , Aravazhi S. , Bernhardi E. , Grivas C. , Wörhoff K. , Pollnau M.
Published: April 2013

Co-doping with optically inert Gd3+ and Lu3+ ions improves refractive-index contrast and light confinement in KY(WO4)2: Yb3+ planar waveguides. Lasing with 18 mW threshold and record-high slope efficiency of 82.3% versus absorbed pump power is demonstrated.
Single-Frequency Wavelength-Tunable Erbium-Doped Fiber Laser with Simple Ring Scheme
Authors: Yeh Chien Hung , Chow Chi Wai
Published: April 2013

We demonstrate a single-longitudinal-mode wavelength-tunable erbium-doped fiber ring laser using simple ring cavity design. Based on the fiber ring design, the mode hopping can be avoided to achieve single-frequency output in C-band operation.
Model-based phase-shaping for SPM-compensation in mJ-pulse-energy fiber CPA-systems
Authors: Schimpf D. N. , Eidam T. , Seise E. , Limpert J. , Tünnermann A.
Published: April 2013

Based on an analytical model for the impact of SPM on stretched ultrashort pulses, the influence of SPM is experimentally controlled in a fiber-based CPA-system. Nearly transform-limited pulses with energies as high as 1 mJ are produced at a B-integral as high as 8 rad. The value of the B-integral is measured by the phase-compensation method. The technique neither relies on complex phase-measurements nor on time-consuming optimization routines.
Pump Induced Loss in Directly-Diode Laser Pumped Ti:Sapphire Lasers
Authors: Maclean Alexander J. , Roth Peter W. , Burns David , Kemp Alan J. , Moulton Peter F.
Published: April 2013

Pump wavelengths of less than 460nm compromise the performance of Ti:sapphire lasers by inducing loss. This – and not pump brightness or absorption – is the primary performance limitation in these lasers.
Ultrafast Laser Inscription of a High Gain Er-doped Bismuthate Glass Waveguide Amplifier
Authors: Thomson R. R. , Beecher S. , Psaila N. D. , Kar A. K.
Published: April 2013

An Er-doped bismuthate glass waveguide amplifier has been fabricated using ultrafast laser inscription. The amplifier exhibits a peak net gain of ≈ 16.5 dB, and > 10.0 dB of net gain across the C-telecommunications band.
High-power Yb-frequency comb using fiber stretcher / grating compressor and linear amplification
Authors: Ruehl A. , Hartl I. , Marcinkevicius A. , Fermann M. E.
Published: April 2013

We report on an Yb-fiber frequency comb laser delivering 155 fs pulses at 65 W compressed average power at a repetition rate of 154 MHz. By designing the group-delay between fiber stretcher and compressor, a compression factor above 4100 could be demonstrated allowing for strictly linear amplification.
Passive mode-locking of a Nd:GdVO4 laser by intracavity SHG in periodically-poled stoichiometric lithium tantalate
Authors: Iliev Hristo , Chuchumishev Danail , Buchvarov Ivan , Kurimura Sunao , Petrov Valentin , Griebner Uwe
Published: April 2013

Stable and self-starting mode-locking is achieved by cascaded second order nonlinearity using PPMgSLT nonlinear crystal in a Nd:GdVO4 laser, achieving average powers up to 5.1 W and pulse durations as short as 3.8 ps.