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Selected AbstractsMagnetostatic analysis of a brushless DC motor using a two-dimensional partial differential equation solverCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 2 2001A. Kostaridis Abstract A finite element, magnetostatic analysis, of a brushless direct current motor containing non-linear materials and permanent magnets is presented. The analysis is performed with PDEaseÔ, a low cost, two-dimensional partial differential equation solver. The descriptor file is remarkably short and easy to understand, enabling students to focus on the application and not on the finite element method. © 2001 John Wiley & Sons, Inc. Comput Appl Eng Educ 9: 93,100, 2001 [source] Clock synchronization in Cell/B.E. tracesCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 14 2009M. Biberstein Abstract Cell/B.E. is a heterogeneous multicore processor that was designed for the efficient execution of parallel and vectorizable applications with high computation and memory requirements. The transition to multicores introduces the challenge of providing tools that help programmers tune the code running on these architectures. Tracing tools, in particular, often help locate performance problems related to thread and process communication. A major impediment to implementing tracing on Cell is the absence of a common clock that can be accessed at low cost from all cores. The OS clock is costly to access from the auxiliary cores and the hardware timers cannot be simultaneously set on all the cores. In this paper, we describe an offline trace analysis algorithm that assigns wall-clock time to trace records based on their thread-local time stamps and event order. Our experiments on several Cell SDK workloads show that the indeterminism in assigning wall-clock time to events is low, on average 20,40 clock ticks (translating into 1.4,2.8,µs on the system used in our experiments). We also show how various practical problems, such as the imprecision of time measurement, can be overcome. Copyright © 2009 John Wiley & Sons, Ltd. [source] High-level distribution for the rapid production of robust telecoms software: comparing C++ and ERLANGCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 8 2008J. H. Nyström Abstract Currently most distributed telecoms software is engineered using low- and mid-level distributed technologies, but there is a drive to use high-level distribution. This paper reports the first systematic comparison of a high-level distributed programming language in the context of substantial commercial products. Our research strategy is to reengineer some C++/CORBA telecoms applications in ERLANG, a high-level distributed language, and make comparative measurements. Investigating the potential advantages of the high-level ERLANG technology shows that two significant benefits are realized. Firstly, robust configurable systems are easily developed using the high-level constructs for fault tolerance and distribution. The ERLANG code exhibits resilience: sustaining throughput at extreme loads and automatically recovering when load drops; availability: remaining available despite repeated and multiple failures; dynamic reconfigurability: with throughput scaling near-linearly when resources are added or removed. Secondly, ERLANG delivers significant productivity and maintainability benefits: the ERLANG components are less than one-third of the size of their C++ counterparts. The productivity gains are attributed to specific language features, for example, high-level communication saves 22%, and automatic memory management saves 11%,compared with the C++ implementation. Investigating the feasibility of the high-level ERLANG technology demonstrates that it fulfils several essential requirements. The requisite distributed functionality is readily specified, even although control of low-level distributed coordination aspects is abrogated to the ERLANG implementation. At the expense of additional memory residency, excellent time performance is achieved, e.g. three times faster than the C++ implementation, due to ERLANG's lightweight processes. ERLANG interoperates at low cost with conventional technologies, allowing incremental reengineering of large distributed systems. The technology is available on the required hardware/operating system platforms, and is well supported. Copyright © 2007 John Wiley & Sons, Ltd. [source] A novel growth method for ZnAl2O4 single crystalsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 3 2006K. Kumar Abstract ZnAl2O4 is a well-known wide band gap compound semiconductor (Eg=3.8eV), ceramic, opto-mechanical, anti-thermal coating in aero-space vehicles and UV optoelectronic devices. A novel method for the growth of single crystals of a ternary oxide material was developed as a fruit of a long term work. Material to be grown as metal incorporated single crystal was taken as precursor and put into a bath containing acid as reaction speed up reagent (catalyst) as well as solvent with a metal foil as cation scavenger. Using this method, ZnAl2O4 crystals having hexagonal facets are prepared from a single optimized bath. Structural and compositional properties of crystals were studied using Philips, Xpert - MPD: X-ray diffractometer and Philips, ESEM-TMP + EDAX. Thus technique was found to be a new low cost and advantageous method for growth of single crystals of ternary oxide a material. We hope that these data be helpful either as a scientific or technical basis in material processing. Dedicated to Prof. P. Ramasamy © 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim [source] Sclerosing Foam in the Treatment of Varicose Veins and Telangiectases: History and Analysis of Safety and ComplicationsDERMATOLOGIC SURGERY, Issue 1 2002Alessandro Frullini MD objective. To review the use of sclerosing foam in the treatment of varicose veins, to describe the different techniques of foam preparation, and to report the complications of our 3-year experience with this treatment. method. From November 1997 to the end of October 2000, 453 patients were treated with a sclerosing foam for large, medium, and minor varicosities with sodium tetradecylsulfate (STS) or polidocanol (POL). A first group of 257 patients (90 for minor varicosities and 167 for medium to large veins) received a sclerosing foam according to the Monfreux technique. From December 1999 to October 2000, 196 patients were treated with a sclerosing foam prepared according to Tessari's method (36 for minor size veins or teleangectasias and 170 for medium-large veins). Every patient was studied with (color-flow) duplex scanning before and after the treatment and large vein injections were administered under duplex guide. results. The immediate success rate was 88.1% in the first group for the medium-large veins. In the same districts we registered an early success rate in 93.3% for the patients treated with the Tessari's method. The complication rate (mostly minor complications) was 8.5% in the first group and 7.1% in the second group. conclusion. The use of sclerosing foam may become an established therapy in the treatment of varicose veins with a high success rate, low cost, and low major complication rate. According to our actual experience and knowledge, the safe amount of foam should not exceed the 3-ml limit, but further advancements could come from standardization of the foam preparation technique. [source] Perfusional evaluation of postesophagectomy gastroplasty with a radioisotopic studyDISEASES OF THE ESOPHAGUS, Issue 6 2008G. Gabiatti SUMMARY., Anastomotic fistula represents one of the frequent causes of postoperative morbidity and mortality following transhiatal esophageal resections. The main etiological factor is the ischemia of the gastric tube created for digestive transit reconstruction. Evidence suggests that per operative hypoperfusion can be maintained or even impaired after the surgery. Several methods have been employed in an attempt to assess the blood perfusion of the gastric flap, but they all pose limitations. However, there is a chronological relationship between perfusion assessments, which are almost exclusively performed per operatively, and the occurrence of a leak, which commonly appears several days after the surgery. The authors have developed a method of gastric perfusion evaluation by single photon emission computed tomography scintigraphy, which corrects that temporal matter, allowing the estimation of postoperative gastric perfusion. It is noninvasive, low cost, and may be applied by the time frame when most fistulas occur. High correlation between the event fistula and the low radiotracer uptake in the group of studied patients could be demonstrated. A role in the research of perfusion evaluation of different types of esophageal reconstruction is suggested. [source] Poppy seed tea and opiate abuse in New ZealandDRUG AND ALCOHOL REVIEW, Issue 2 2007KLARE BRAYE Abstract The opium poppy Papaver somniferum contains an array of opiates. There is a variety of methods of preparation that can be used by people with opiate dependence, with patterns of use determined by numerous factors including cost, safety, potency and legal status. The objective of this study was to determine the frequency and nature of poppy seed tea (PST) use by opiate-dependent patients in the form of a written questionnaire. The study took place at the Community Alcohol and Drug Clinic, Wellington, New Zealand, and comprised 24 opiate-dependent patients attending the clinic. A total of 11 of 24 (46%) patients reported having used PST. In five patients currently using PST it represented the major source of opiates, and two had managed to withdraw from use of other opiates with regular PST use. Patients reported a median onset of action of 15 minures and an effect lasting a median of 24 hours. The major limitation of PST use was the foul taste. PST is used commonly by opiate-dependent patients attending an alcohol and drug clinic in New Zealand. The use of PST as the major source of opiates could be considered favourably within ,harm reduction' philosophies, because of its low cost, legal availability and oral route of administration. Conversely, there is the potential for PST to act as a ,gateway drug' by inducing opioid dependence and introducing people to the culture of drug abuse. [source] Financial Innovation and the Transactions Demand for CashECONOMETRICA, Issue 2 2009Fernando Alvarez We document cash management patterns for households that are at odds with the predictions of deterministic inventory models that abstract from precautionary motives. We extend the Baumol,Tobin cash inventory model to a dynamic environment that allows for the possibility of withdrawing cash at random times at a low cost. This modification introduces a precautionary motive for holding cash and naturally captures developments in withdrawal technology, such as the increasing diffusion of bank branches and ATM terminals. We characterize the solution of the model, which qualitatively reproduces several empirical patterns. We estimate the structural parameters using micro data and show that quantitatively the model captures important economic patterns. The estimates are used to quantify the expenditure and interest rate elasticity of money demand, the impact of financial innovation on money demand, the welfare cost of inflation, and the benefit of ATM ownership. [source] From privatized to government-administered tax collection: tax farming in eighteenth-century France1ECONOMIC HISTORY REVIEW, Issue 4 2004EUGENE N. WHITE The establishment of a government bureaucracy to collect taxes is regarded as one of the essential features of a modern economy. While Britain is considered a pioneer, France has been treated as a laggard because of continued reliance on tax farming. Focusing on the largest tax farm, France's late transition from private to government tax collection is explained in a principal-agent context by the difficulties of monitoring employees and borrowing at low cost in the capital market. Tax farmers continued to earn high returns, absorbing the risk of fluctuating collections, leaving the Crown with lower revenue. [source] European industry: the emerging market competitiveness challengeECONOMIC OUTLOOK, Issue 3 2006Article first published online: 24 AUG 200 As the global economy has become increasingly open to 'free' trade, European industry - and, indeed, industry across the developed world - has found itself faced with growing competition from low cost, emerging market countries. How is it facing up to this stiff challenge? Newspaper headlines may suggest that effort has been focused on raising trade barriers to keep competition at bay. However, such actions are a thin veneer over the very real, structural changes that are rapidly taking place. This article, by Grant Colquhoun, examines the changing structure of the EU15's trading patterns and the differential impact across manufacturing sectors. It then analyses the steps industry is taking to cope with the competitiveness challenge. As well as attempting to squeeze costs, it is clear that industry in Europe is restructuring in order to focus on higher value added activities, where it typically has a competitive advantage over emerging markets. [source] Fabrication, Characterization, and Application of ,Sandwich-Type' Electrode Based on Single-Walled Carbon Nanotubes and Room Temperature Ionic LiquidELECTROANALYSIS, Issue 17 2008Xuzhi Zhang Abstract The much-enhanced electrochemical responses of potassium ferricyanide and methylene blue (MB) were firstly explored at the glassy carbon electrode modified with single-walled carbon nanotubes (SWNT/GCE), indicating the distinct electrochemical activity of SWNTs towards electroactive molecules. A hydrophobic room temperature ionic liquid (RTIL), 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6), was used as electrode modification material, which presented wide electrochemical windows, proton permeation and selective extraction ability. In consideration with the advantages of SWNTs and RTIL in detecting target molecules (TMs), a novel strategy of ,sandwich,type' electrode was established with TMs confined by RTIL between the SWNT/GCE and the RTIL membrane. The strategy was used for electrochemical detection of ascorbic acid (AA) and dopamine (DA), and detection limits of 400 and 80 fmol could be obtained, respectively. The selective detection of DA in the presence of high amount of AA could also be realized. This protocol presented many attractive advantages towards voltammetric detection of TMs, such as low sample demand, low cost, high sensitivity, and good stability. [source] Label-Free Impedance Biosensors: Opportunities and ChallengesELECTROANALYSIS, Issue 12 2007Jonathan Abstract Impedance biosensors are a class of electrical biosensors that show promise for point-of-care and other applications due to low cost, ease of miniaturization, and label-free operation. Unlabeled DNA and protein targets can be detected by monitoring changes in surface impedance when a target molecule binds to an immobilized probe. The affinity capture step leads to challenges shared by all label-free affinity biosensors; these challenges are discussed along with others unique to impedance readout. Various possible mechanisms for impedance change upon target binding are discussed. We critically summarize accomplishments of past label-free impedance biosensors and identify areas for future research. [source] Disposable Screen-Printed Edge Band Ultramicroelectrodes for the Determination of Trace Amounts of Nitrite IonELECTROANALYSIS, Issue 10 2006Jen-Lin Chang Abstract The application of linear scan voltammetry for sensitive determination of nitrite by using a disposable screen-printed edge band carbon ultramicroelectrode (designated as SPUME) was reported in this study. The measurement with the SPUME can be performed in solutions of low ionic strength, e.g., natural waters, because the ohmic loses are negligible. The limiting oxidation current of nitrite showed a wide linear range up to 3,mM at the SPUME. A relative standard deviation of 2.46% (n=5) for analyzing 5,,M nitrite indicated a detection limit (S/N=3) of 0.38,,M. Real sample analysis of mineral and ground water samples as well as bratwurst food product showed satisfactory results. Since the SPUME is low cost and easy for mass production, the disposable nature further offers to application in diverse field of electroanalytical chemistry. [source] Recent Advances in Electrochemical Enzyme ImmunoassaysELECTROANALYSIS, Issue 21 2005María Díaz-González Abstract Enzyme immunoassays (EIAs) are currently the predominant analytical technique for the quantitative determination of a broad variety of analytes in clinical, medical, biotechnological, and environmental significance. Although the most common detection methods for EIAs are based on spectroscopic measurements, electrochemical techniques, due to their high sensitivity, selectivity, simplicity and low cost, have emerged as a very attractive alternative to carry out the detection step in this kind of assays. The intention of this review is to cover the progress and development in integrating electrochemical detection methods with EIAs, over the past five years. [source] Electrochemical Detection for Capillary Electrophoresis Microchips: A ReviewELECTROANALYSIS, Issue 13 2005Joseph Wang Abstract Electrochemistry detection offers considerable promise for capillary-electrophoresis (CE) microchips, with features that include remarkable sensitivity, portability, independence of optical path length or sample turbidity, low cost and power requirements, and high compatibility with modern micromachining technologies. This article highlights key strategies in controlled-potential electrochemical detectors for CE microchip systems, along with recent advances and directions. Subjects covered include the design of the electrochemical detection system, its requirements and operational principles, common electrode materials, isolation from the separation voltage, derivatization reactions, typical applications, and future prospects. It is expected that electrochemical detection will become a powerful tool for CE microchip systems and will lead to the creation of truly portable (and possibly disposable) devices. [source] DNA Hybridization at Magnetic Nanoparticles with Electrochemical Stripping DetectionELECTROANALYSIS, Issue 23 2004Ningning Zhu Abstract A simple and practical method for electrochemical DNA hybridization assay has been developed to take advantage of magnetic nanoparticles for ssDNA immobilization and zinc sulfide nanoparticle as oligonucleotide label. Magnetic nanoparticles were prepared by coprecipitation of Fe2+ and Fe3+ with NH4OH, and then amino silane was coated onto the surface of magnetite nanoparticles. The magnetic nanoparticles have the advantages of easy preparation, easy surface modification and low cost. The target ssDNA with the phosphate group at the 5, end was then covalently immobilized to the amino group of magnetite nanoparticles by forming a phosphoramidate bond in the presence of 1-ethyl-3-(3-dimeth-ylaminopropyl)carbodiimide (EDAC). The zinc sulfide (ZnS) nanoparticle-labeled oligonucleotides probe was used to identify the target ssDNA immobilized on the magnetic nanoparticles based on a specific hybridization reaction. The hybridization events were assessed by the dissolution of the zinc sulfide nanoparticles anchored on the hybrids and the indirect determination of the dissolved zinc ions by anodic stripping voltammetry (ASV) at a mercury film glassy carbon electrode (GCE). The proposed method couples the high sensitivity of anodic stripping analysis for zinc ions with effective magnetic separation for eliminating nonspecific adsorption effects and offers great promise for DNA hybridization analysis. [source] A simple light-emitted diode-induced fluorescence detector using optical fibers and a charged coupled device for direct and indirect capillary electrophoresis methodsELECTROPHORESIS, Issue 9 2006David Arráez-Román Abstract We constructed a simple fluorescence detector for both direct and indirect CE methods using a blue light-emitted diode (470,nm) as excitation source, a bifurcated optical fiber as a waveguide, and a CCD camera as a detector. The connection of all the components is fairly easy even for nonexperts and the use of a CCD camera improves the applicability of this detector compared to the others using PMTs because it permits the recording of 2-D electropherograms or phosphorescence measurements. This detector provides a compact, low cost, and rapid system for the determination of native fluorescence compounds which have high quantum yields by CE with direct fluorescence detection, showing an LOD of 2.6×10,6,M for fluorescein; the determination of fluorescence derivative compounds by CE with direct fluorescence detection, showing an LOD of 1.6×10,7,M for FITC-labeled 1,6-diaminohexane; and nonfluorescence compounds by CE with indirect fluorescence detection with an LOD of 2.7×10,6,M for gallic acid. [source] Does the standard intravenous solution of fentanyl (50 µg/mL) administered intranasally have analgesic efficacy?EMERGENCY MEDICINE AUSTRALASIA, Issue 1 2010Dianne Crellin Abstract Background: Intranasal (IN) fentanyl provides rapid and powerful non-parenteral analgesia in the ED. A concentrated solution of fentanyl (300 µg/mL) has been used in prior trials, yet many ED use the standard solution at a concentration of 50 µg/mL, which is widely available and of low cost. We set out to determine if this lower concentration of fentanyl is also efficacious. Methods: Prospective audit in children aged 5,18 years presenting with upper limb injuries. Patients received IN fentanyl (50 µg/mL) at 1.5 µg/kg. Patient assessed pain scores were collected 5, 10, 20, 30 and 60 min following IN fentanyl administration using a visual analogue scale or Bieri Faces , Revised scale. Parental scores were used if patients were unable to provide a score. Results: Of the 59 eligible patients, 36 were enrolled; median age was 6.8 years (range 5,15 years), and 89% (32/36) ultimately required fracture reduction. Median first dose of IN fentanyl was 1.4 µg/kg. Median pain scores dropped from 7 (interquartile range 5,10) pre-fentanyl to 5 (interquartile range 4,8) at 5 min and 2 (interquartile range 1,4) at 30 and 60 min. A total of 21 (58%) children did not require further analgesia in the ED. There were no adverse events. Conclusions: Standard i.v. concentration IN fentanyl (50 µg/mL) appears to have analgesic efficacy in children with upper limb injuries. [source] A new rapid micromethod for the assay of phenobarbital from dried blood spots by LC-tandem mass spectrometryEPILEPSIA, Issue 12 2009Giancarlo La Marca Summary Advantages of dried blood spot include low invasiveness, ease and low cost of sample collection, transport, and storage. We used tandem mass spectrometry (LC-MS/MS) to determine phenobarbital levels on dried blood spot specimens and compared this methodology to commercially available particle enhanced turbidimetric inhibition immunoassay (PETINIA) in plasma/serum samples. The calibration curve in matrix using D5 -phenobarbital as internal standard was linear in the phenobarbital concentration range of 1,100 mg/L (correlation coefficient 0.9996). The coefficients of variation in blood spots ranged 2.29,6.71% and the accuracy ranged 96.54,103.87%. There were no significant differences between the concentrations measured using PETINA and LC-MS/MS (both had similar precision and accuracy) however, LC-MS/MS allows at least 1.5 times higher throughput of phenobarbital analysis and additionally offers ease of sample collection which is particularly important for newborns or small infants. [source] Adding Video Recording Increases the Diagnostic Yield of Routine Electroencephalograms in Children with Frequent Paroxysmal EventsEPILEPSIA, Issue 5 2005Nathan Watemberg Summary:,Purpose: To report on the usefulness of adding video recording to routine EEG studies of infants and children with frequent paroxysmal events. Methods: We analyzed the efficacy of this diagnostic means during a 4-year period. The decision whether to add video recording was made by the pediatric EEG interpreter at the time of the study. Studies were planned to last between 20 and 30 min, and, if needed, were extended by the EEG interpreter. For most studies, video recording was added from the beginning of EEG recording. In a minority of cases, the addition of video was implemented during the first part of the EEG test, as clinical events became obvious. In these cases, a new study (file) was begun. The success rate was analyzed according to the indications for the EEG study: paroxysmal eye movements, tremor, suspected seizures, myoclonus, staring episodes, suspected stereotypias and tics, absence epilepsy follow-up, cyanotic episodes, and suspected psychogenic nonepileptic events. Results: Video recording was added to 137 of 666 routine studies. Mean patient age was 4.8 years. The nature of the event was determined in 61 (45%) of the EEG studies. Twenty-eight percent were hospitalized patients. The average study duration was 26 min. This diagnostic means was particularly useful for paroxysmal eye movements, staring spells, myoclonic jerks, stereotypias, and psychogenic nonepileptic events. About 46% of 116 patients for whom cognitive data were available were mentally retarded. EEG with added video recording was successfully performed in all 116 cases and provided useful information in 29 (55%) of these 53 patients. Conclusions: Adding video recording to routine EEG was helpful in 45% of cases referred for frequent paroxysmal events. This technique proved useful for hospitalized children as well as for outpatients. Moreover, it was successfully applied in cognitively impaired patients. Infants and children with paroxysmal eye movements, staring spells, myoclonic jerks, stereotypias, and pseudoseizures especially benefited from this diagnostic means. Because of its low cost and the little discomfort imposed on the patient and his or her family, this technique should be considered as a first diagnostic step in children with frequent paroxysmal events. [source] Traditional Chinese medicine in cancer care: perspectives and experiences of patients and professionals in ChinaEUROPEAN JOURNAL OF CANCER CARE, Issue 4 2006W. XU md, msc Although traditional Chinese medicine (TCM) is widely used in Chinese cancer centres, it is a brand new area for formal scientific evaluation. As the first step of developing a research programme on clinical evaluation of TCM for cancer patients, we conducted a qualitative study to explore the perspectives and experiences of Chinese cancer patients and TCM professionals. Twenty-eight persons participated in two cancer patient focus groups and one professional focus group. Semi-structured interviews were audiotaped, transcribed and translated. Textual transcripts and field notes underwent inductive thematic analysis. We found that patients' decision to use TCM for cancer is a self-help process with a deep cultural grounding, which is related to the traditional Chinese philosophy of life. Participants perceived TCM to be an effective and harmless therapy. They highly valued the fact that TCM is tailored to patients, and believed it was the basis of an optimal and safe treatment. Participants also highlighted the long-term positive effects, the benefit of group interventions and the low cost as important features of TCM. Subjects believed that conducting clinical research would be crucial for the recognition and dissemination of TCM in Western countries. The findings of this study are expected to contribute to the knowledge base on the current TCM use for cancer in China, and to provide useful information for developing future clinical research in this area in Western countries. [source] Antioxidant capacity of rapeseed meal and rapeseed oils enriched with meal extractEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7 2010Aleksandra Szyd, owska-Czerniak Abstract Response surface methodology (RSM) was used to evaluate the quantitative effects of two independent variables: solvent polarity and temperature of the extraction process on the antioxidant capacity (AC) and total phenolics content (TPC) in meal rapeseed extracts. The mean AC and TPC results for meal ranged between 1181,9974,µmol TE/100,g and 73.8,814,mg sinapic acid/100,g of meal. The experimental results of AC and TPC were close to the predicted values calculated from the polynomial response surface models equations (R2,=,0.9758 and 0.9603, respectively). The effect of solvent polarity on AC and TPC in the examined extracts was about 3.6 and 2.6 times greater, respectively, than the effect of processing temperature. The predicted optimum solvent polarity of ,,=,78.3 and 63.8, and temperature of 89.4 and 74.2°C resulted in an AC of 10,014,µmol TE/100,g and TPC of 863,mg SAE/100,g meal, respectively. The phenolic profile of rapeseed meal was determined by an HPLC method. The main phenolics in rapeseed meal were sinapine and sinapic acid. Refined rapeseed oils were fortified with an extract , rich in polyphenols , obtained from rapeseed meal. The supplemented rapeseed oil had higher AC and TPC than the refined oil without addition of meal extracts. However, AC and TPC in the enriched oils decreased during storage. The TPC in the studied meal extracts and rapeseed oils correlated significantly (p<0.0000001) positively with their AC (R2,=,0.9387). Practical applications: Many bioactive compounds extracted from rapeseed meal provide health benefits and have antioxidative properties. Therefore, it seems worth to consider the application of antioxidants extracted from the rapeseed meal for the production of rapeseed oils with potent AC. Moreover, antioxidants extracted from the rapeseed meal were added to refined rapeseed oil in order to enhance its AC. AC was then tested by FRAP assay. FRAP method is based on the reduction of the ferric tripyridyltriazine (Fe3+ -TPTZ) complex to the ferrous tripyridyltriazine (Fe2+ -TPTZ), and it is simple, fast, low cost, and robust method. FRAP method does not require specialized equipment and can be performed using automated, semi-automatic, or manual methods. Therefore the proposed FRAP method can be employed by the fat industry laboratories to asses the AC of rapeseed oils and meal. [source] Spill-over effects of intermittent costs for defection in social dilemmasEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 6 2002Daniel Eek This research investigates the role of intermittent monetary costs in restraining individuals from defection in social dilemmas. In Experiment 1, 104 car owners made fictitious choices between a slow and a fast travel mode in the context of a continuous social dilemma. There were four different conditions of monetary costs for choosing the fast mode (defection): no cost, low cost, high cost to self, or high cost to others. Participants defected most when there was no cost and least when they themselves were charged a high cost. A spill-over effect was obtained such that when others were charged a high cost to defect, defection rates were lower than under no cost. Experiment 2 used 36 undergraduates as participants in an iterated decision task with real groups. The results replicated the major results of Experiment 1. Furthermore, whereas prosocials were strongly affected by intermittent costs for defection (i.e. showed large spill-over effects), proselfs seemed to be unaffected. Possible explanations of this interaction effect between social value orientation and intermittent punishment for defection are provided. Copyright © 2002 John Wiley & Sons, Ltd. [source] Enhanced Ductility of Dendrite-Ultrafine Eutectic Composite Fe3B Alloy Prepared by a Self-Propagating High-Temperature Synthesis,ADVANCED ENGINEERING MATERIALS, Issue 3 2009Licai Fu The bulk dendrite-ultrafine eutectic composite Fe3B alloy was prepared by a self-propagating high-temperature synthesis. This technique is convenient, low cost, and capable of being scaled up for processing bulk nano/ultrafine-structured materials. The Fe3B alloy is composed of a micrometer-sized dendrite dispersed in an ultrafine laminar eutectic matrix and exhibits both high strength and large ductility in compressive tests. [source] Volume Organization of Polymer and Hybrid Solar Cells as Revealed by Electron TomographyADVANCED FUNCTIONAL MATERIALS, Issue 19 2010Svetlana S. van Bavel Abstract Polymer and hybrid solar cells have the potential to become the leading technology of the 21st century in conversion of sun light to electrical energy because their ease processing from solution producing printable devices in a roll-to-roll fashion with high speed and low cost. The performance of such devices critically depends on the nanoscale organization of the photoactive layer, which is composed of at least two functional materials: the electron donor and the electron acceptor forming a so-called bulk heterojunction; however, control of its volume morphology still is a challenge. In this context, advanced analytical tools are required that are able to provide information on the local volume morphology of the photoactive layer with nanometer resolution. In this report electron tomography is introduced as the technique able to explore the 3D morphology of polymer and hybrid solar cells and the first results achieved are critically discussed. [source] Non-Corrosive, Non-Absorbing Organic Redox Couple for Dye-Sensitized Solar CellsADVANCED FUNCTIONAL MATERIALS, Issue 19 2010Dongmei Li Abstract A new colorless electrolyte containing an organic redox couple, tetramethylthiourea (TMTU) and its oxidized dimer tetramethylformaminium disulfide dication ([TMFDS]2+), is applied to dye-sensitized solar cells (DSCs). Advantages of this redox couple include its non-corrosive nature, low cost, and easy handling. More impressively, it operates well with carbon electrodes. The DSCs fabricated with a lab-made HCS-CB carbon counter-electrode can present up to 3.1% power conversion efficiency under AM 1.5 illumination of 100 mW·cm,2 and 4.5% under weaker light intensities. This result distinctly outperforms the identical DSCs with a Pt electrode. Corrosive experiments reveal that Al and stainless steel (SS) sheets are stable in the [TMFDS]2+/TMTU-based electrolyte. Its electrochemical impedance spectrum (EIS) is used to evaluate the influence of different counter-electrodes on the cell performance, and preliminary investigations reveal that carbon electrodes with large surface areas and ideal corrosion-inertness toward the sulfur-containing [TMFDS]2+/TMTU redox couple exhibit promise for application in iodine-free DSCs. [source] Interface Engineering for Organic ElectronicsADVANCED FUNCTIONAL MATERIALS, Issue 9 2010Hong Ma Abstract The field of organic electronics has been developed vastly in the past two decades due to its promise for low cost, lightweight, mechanical flexibility, versatility of chemical design and synthesis, and ease of processing. The performance and lifetime of these devices, such as organic light-emitting diodes (OLEDs), photovoltaics (OPVs), and field-effect transistors (OFETs), are critically dependent on the properties of both active materials and their interfaces. Interfacial properties can be controlled ranging from simple wettability or adhesion between different materials to direct modifications of the electronic structure of the materials. In this Feature Article, the strategies of utilizing surfactant-modified cathodes, hole-transporting buffer layers, and self-assembled monolayer (SAM)-modified anodes are highlighted. In addition to enabling the production of high-efficiency OLEDs, control of interfaces in both conventional and inverted polymer solar cells is shown to enhance their efficiency and stability; and the tailoring of source,drain electrode,semiconductor interfaces, dielectric,semiconductor interfaces, and ultrathin dielectrics is shown to allow for high-performance OFETs. [source] Quantum-Dot-Tagged Bioresponsive Hydrogel Suspension Array for Multiplex Label-Free DNA DetectionADVANCED FUNCTIONAL MATERIALS, Issue 6 2010Yuanjin Zhao Abstract A novel hydrogel suspension array, which possesses the joint advantages of quantum-dot-encoded technology, bioresponsive hydrogels, and photonic crystal sensors with full multiplexing label-free DNA detection capability is developed. The microcarriers of the suspension array are quantum-dot-tagged DNA-responsive hydrogel photonic beads. In the case of label-free DNA detection, specific hybridization of target DNA and the crosslinked single-stranded DNA in the hydrogel grid will cause hydrogel shrinking, which can be detected as a corresponding blue shift in the Bragg diffraction peak position of the beads that can be used for quantitatively estimating the amount of target DNA. The results of the label-free DNA detection show that the suspension array has high selectivity and sensitivity with a detection limit of 10,9,M. This method has the potential to provide low cost, miniaturization, and simple and real-time monitoring of hybridization reaction platforms for detecting genetic variations and sequencing genes. [source] Measuring metabolic rate in the field: the pros and cons of the doubly labelled water and heart rate methodsFUNCTIONAL ECOLOGY, Issue 2 2004P. J. Butler Summary 1Measuring the metabolic rate of animals in the field (FMR) is central to the work of ecologists in many disciplines. In this article we discuss the pros and cons of the two most commonly used methods for measuring FMR. 2Both methods are constantly under development, but at the present time can only accurately be used to estimate the mean rate of energy expenditure of groups of animals. The doubly labelled water method (DLW) uses stable isotopes of hydrogen and oxygen to trace the flow of water and carbon dioxide through the body over time. From these data, it is possible to derive a single estimate of the rate of oxygen consumption () for the duration of the experiment. The duration of the experiment will depend on the rate of flow of isotopes of oxygen and hydrogen through the body, which in turn depends on the animal's size, ranging from 24 h for small vertebrates to up to 28 days in Humans. 3This technique has been used widely, partly as a result of its relative simplicity and potential low cost, though there is some uncertainty over the determination of the standard error of the estimate of mean . 4The heart rate (fH) method depends on the physiological relationship between heart rate and . 5If these two quantities are calibrated against each other under controlled conditions, fH can then be measured in free-ranging animals and used to estimate . 6The latest generation of small implantable data loggers means that it is possible to measure fH for over a year on a very fine temporal scale, though the current size of the data loggers limits the size of experimental animals to around 1 kg. However, externally mounted radio-transmitters are now sufficiently small to be used with animals of less than 40 g body mass. This technique is gaining in popularity owing to its high accuracy and versatility, though the logistic constraint of performing calibrations can make its use a relatively extended process. [source] Medicinal plants and the treatment of diabetes in Senegal: survey with patientsFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 2 2008Amadou Moctar Dièye Abstract Diabetes is the most common metabolic disorder worldwide and is a major public health problem. Its frequency increases every day in all countries. However, in developing African countries, few people have access to drugs. In addition, in Africa, traditional beliefs induce people to use medicinal plants whenever they have health problems. Thus, many people in these developing countries use plants for the treatment of diabetes. Yet, few studies are focused on the knowledge and attitudes of the users on medicinal plants in Africa in general and in Senegal in particular. Hence we undertook this survey on the use of medicinal plants for the treatment of diabetes in Senegal in order to make recommendations which could contribute to the increase of the value of herbal medicines in developing countries. We did a cross-sectional survey by direct interview at a university teaching hospital, in Dakar with a representative sample of 220 patients. Forty-one plants were used by the patients and the two most frequently cited were Moringa oleifera Lam (65.90%) and Sclerocarya birrea (A. Rich) Hochst (43.20%). Patients gave several reasons for using medicinal plants (traditional treatment: 40%, efficacy: 32%, low cost: 20%). The principal suppliers of plants were tradesmen in the market (66.8%) and traditional therapists (5%). Sixty-five per cent of patients think that medicinal plants are efficient for the treatment of diabetes and 20% have reported adverse effects which could be caused by medicinal plants. In conclusion, many people in our study think that medicinal plants are efficient for the treatment of diabetes, which requires research work by scientists in developing countries in this field in order to prove their efficacy and innocuousness. [source] | ||||||||||||||||||||||||||||||||||||||||