New Approach (new + approach)

Distribution by Scientific Domains

Kinds of New Approach

  • possible new approach
  • promising new approach
  • several new approach


  • Selected Abstracts


    WHEN MISSING DATA ARE NOT MISSING: A NEW APPROACH TO EVALUATING SUPPLEMENTAL HOMICIDE REPORT IMPUTATION STRATEGIES,

    CRIMINOLOGY, Issue 4 2008
    TIM WADSWORTH
    The Supplemental Homicide Reports (SHR) are widely used in criminological research and inform a broad range of research topics and subsequent policy applications. A serious issue with the SHR is missing information about the offender and incident in many recorded homicides. Although it is convenient to discard cases with missing data before analysis, such discarding is not theoretically justified and can lead to incorrect substantive conclusions. Recently, several techniques for imputing missing SHR data have been proposed, but it is difficult to evaluate their effectiveness. This research presents a new approach to testing and evaluating SHR imputation techniques. Offender data that are missing in the SHR are often found in police records available for individual cities. We examine similarities and differences among cases with known offender characteristics in the SHR, cases with such information missing in the SHR but available in police records, and cases with such information missing in both sources. We then use these data sets to evaluate four different imputation techniques suggested in the literature (Fox, 2004; Messner, Deane, and Beaulieu, 2002; Pampel and Williams, 2000; Regoeczi and Riedel, 2003). We apply each imputation technique to the SHR, and for cases with information missing in the SHR but known in the police records, we see how well the imputed values correspond both with the individual known values and with the overall distributions in the police records. We discuss the outcome of our assessment of these strategies, and we outline important implications this assessment has for research using SHR data. [source]


    A NEW APPROACH TO TEACHING EVOLUTION

    EVOLUTION, Issue 6 2010
    Judith L. Bronstein
    No abstract is available for this article. [source]


    A NEW APPROACH TO MODELING AND CONTROL OF A FOOD EXTRUSION PROCESS USING ARTIFICIAL NEURAL NETWORK AND AN EXPERT SYSTEM

    JOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2001
    OTILIA POPESCU
    ABSTRACT The paper presents a new approach to the modeling of the start-up part of a food extrusion process. A neural network model is proposed and its parameters are determined. Simulation results with real data are also presented. The inputs and outputs of the model are among those used by the human operator during the start-up process for control. An intelligent controller structure that uses an expert system and "delta-variations" to modify inputs is also proposed. [source]


    A NEW APPROACH TO CORRELATE TEXTURAL AND COOKING PARAMETERS WITH OPERATING CONDITIONS DURING DOUBLE-SIDED COOKING OF MEAT PATTIES

    JOURNAL OF TEXTURE STUDIES, Issue 5 2000
    SUSANA E. ZORRILLA
    Cooking and textural parameters during double-sided cooking of hamburger patties were correlated with volume-averaged temperature at the end of the cooking process and gap thickness between plates. Frozen patties were cooked in a clamshell grill set at different plate surface temperatures (177C; 191C; 204C; 218C), for different gap thicknesses (9.65 mm; 10.55 mm; 10.55 mm; 11.05 mm) for 120 s. A decrease in the gap thickness and an increase in the plate surface temperature resulted in an increase in the cooking loss values (24,36%) and in a decrease of press juice values (8,25%). The values of peak load (183,215 N), modulus (16,19 N/mm), work needed in shearing (2300,2800 Nmm), hardness (25,32 N), cohesiveness (0.76,0.83), and chewiness (107,152 Nmm) of the patties increased when the gap thickness decreased and the plate surface temperature increased. There was no effect of the variables studied on springiness. The correlation equations involving the operating variables and quality parameters obtained are simple and useful in developing optimal process conditions. [source]


    TOWARDS A NEW APPROACH TO ARCHAEOMAGNETIC DATING IN EUROPE USING GEOMAGNETIC FIELD MODELLING*

    ARCHAEOMETRY, Issue 2 2009
    A. LODGE
    We introduce a new approach to producing secular variation curves for archaeomagnetic dating, using global geomagnetic field modelling techniques. Using published palaeosecular variation curves for five European locations as input, and a previous global model for regularization, we produce a model for the period ad 0,1900, which reproduces the input curves within their 95% confidence intervals, and successfully fits data from other regions in Europe. Our global model performs as well as a previous regional model, but additionally ensures consistency with physical constraints. We show that the curves currently used for dating are not mutually consistent, and therefore that in the future this new approach will provide more reliable curves for archaeomagnetic dating. [source]


    A New Approach for Health Monitoring of Structures: Terrestrial Laser Scanning

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 1 2007
    H. S. Park
    Three-dimensional (3D) coordinates of a target structure acquired using TLS can have maximum errors of about 10 mm, which is insufficient for the purpose of health monitoring of structures. A displacement measurement model is presented to improve the accuracy of the measurement. The model is tested experimentally on a simply supported steel beam. Measurements were made using three different techniques: (1) linear variable displacement transducers (LVDTs), (2) electric strain gages, and (3) a long gage fiber optic sensor. The maximum deflections estimated by the TLS model are less than 1 mm and within 1.6% of those measured directly by LVDT. Although GPS methods allow measurement of displacements only at the GPS receiver antenna location, the proposed TLS method allows measurement of the entire building's or bridge's deformed shape, and thus a realistic solution for monitoring structures at both structure and member level. Furthermore, it can be used to create a 3D finite element model of a structural member or the entire structure at any instance of time automatically. Through periodic measurements of deformations of a structure or a structural member and performing inverse structural analyses with the measured 3D displacements, the health of the structure can be monitored continuously. [source]


    Catheter-Assisted Vein Sclerotherapy: A New Approach for Sclerotherapy of the Greater Saphenous Vein with a Double-Lumen Balloon Catheter

    DERMATOLOGIC SURGERY, Issue 4 2007
    JENS P. BRODERSEN MD
    OBJECTIVE We sought to optimize sclerotherapy of the greater saphenous vein (GSV) by targeted application of foamed sclerosant by using a catheter. METHODS We designed a new double-lumen catheter that is inserted into the GSV. Via one lumen, a balloon at the tip of the catheter can be inflated to stop the blood flow. Via the second lumen, the sclerosing agent can be injected and aspirated. This method enabled us to perform a targeted application of the sclerosing agent [catheter-assisted vein sclerotherapy (KAVS)]. In an open study, outpatients suffering from varicosis of the GSV received a foam sclerotherapy under ultrasound guidance, using the newly developed KAVS catheter. RESULTS Thirty patients with an insufficiency (reflux) of the GSV were treated with the newly developed KAVS method using foamed polidocanol. The intervention was well tolerated in all patients without the occurrence of serious side effects. In 27 of the 30 treated patients (90%), we found a closure of the GSV at control visits 6 weeks, 3 months, and 6 months after treatment. CONCLUSIONS The KAVS method represents a feasible approach for sclerotherapy of the GSV. The efficiency and treatment modalities need to be explored in further studies. [source]


    Donor Harvesting: A New Approach to Minimize Transection of Hair Follicles

    DERMATOLOGIC SURGERY, Issue 4 2000
    Damkerng Pathomvanich MD
    Background. There are several methods for harvesting donor hairs, including punch excision, single-bladed knife excision, and multibladed knife excision. All of these procedures are blind and thus result in transection of hair follicles. Transection of hair follicles during harvesting results in fewer follicles being available for transplantation, detrimentally affecting the final cosmetic result. Objective. To explore a new method of donor hair harvesting called "donor dissecting." This new procedure is an open technique because hair follicles are directly visualized during the harvesting process. Methods. The technique of donor dissecting utilizes a #15 scalpel blade to excise the donor hair ellipse from the occiput while maintaining meticulous hemostasis. This enables individual hair follicles to be visualized and protected from transection during the harvesting process. Once the donor ellipse is harvested, it is then further divided into individual mini- and micrografts using direct visualization of individual follicles to again prevent transection. Results. The technique of donor dissecting was utilized in 50 consecutive hair transplant patients. Utilizing this new technique, only 1.9% of hair follicles in the donor ellipse were transected during the harvesting process. The dissection of the donor ellipse 1.2% follicles being transected in the graft cutting process. Combining the donor dissection technique with dissection of the individual grafts, we were able to transect 1.59% of hair follicles harvested for transplantation. Conclusion. The technique of donor dissection minimizes the transection of hair follicles in the donor hair harvesting phase of hair transplantation. This technique is superior to the blind methods of donor harvesting which have been plagued by the problem of hair follicle transection. [source]


    German Castles, Customs, and Culture: Introducing a New Approach to the Undergraduate Culture Course

    DIE UNTERRICHTSPRAXIS/TEACHING GERMAN, Issue 2 2008
    John F. Lalande II
    Courses on the culture of the German-speaking world (GSW) have long dotted the landscape of undergraduate course offerings at North American colleges and universities. The primary purpose of this article is to share information about a new kind of undergraduate culture course that uses castles as a vehicle for introducing students to past and present aspects of GSW culture. [source]


    In Vitro Validation of a New Approach for Quantitating Regurgitations Using Proximal Isovelocity Surface Area

    ECHOCARDIOGRAPHY, Issue 7 2000
    A. Delouche
    The present work has been designed to validate the calculation of the effective regurgitant orifice (ERO) area with the use of a new formula that takes into account the velocity profile (Vr vs r) and that is insensitive to errors in the determination of the position of the orifice. Assuming a hemispheric model, ERO = 2,r2· Vr/Vo (with Vo= velocity at the orifice) and (Vo/Vr)0.5= (2,/ERO)0.5r. Thus, the slope of the corresponding linear regression allows ERO to be calculated as: ERO = 2,/slope2. This approach was tested in vitro in pulsatile conditions on circular, conical, and slit-like orifices. The calculated ERO was compared with the actual jet cross sectional area derived from the transverse velocity profile at the jet origin. For the purpose of comparison, the "classical" ERO was calculated for all the configurations, angulations, and threshold velocities. The relationship between (Vo/Vr)0.5 was linear (r > 0.98) over a wide range of velocities. The nonhemispheric components were found to modify the constant and not the slope. The mean variation of the calculated ERO was 6.5%. The correlation between the calculated and the actual ERO was very close (>0.97) with slope equal to 0.96. By comparison with the new method, the classical formula gave an underestimation of the ERO that dramatically increased when studying the flow closer to the orifice or in the case of error on the measurement of r. In conclusion, a method using velocity profiles instead of isolated values improves the accuracy of the proximal isovelocity surface area (PISA) method for measuring the ERO. [source]


    Stable Non-Covalent Large Area Patterning of Inert Teflon-AF Surface: A New Approach to Multiscale Cell Guidance,

    ADVANCED ENGINEERING MATERIALS, Issue 6 2010
    Francesco Valle
    Micro- and nano-patterning of cell adhesion proteins is demonstrated to direct the growth of neural cells, viz. human neuroblastoma SHSY5Y, at precise positions on a strongly antifouling substrate of technolological interest. We adopt a soft-lithographic approach with oxygen plasma modified PDMS stamps to pattern human laminin on Teflon-AF films. These patterns are based on the interplay of capillary forces within the stamp and non-covalent intermolecular and surface interactions. Remarkably, they remain stable for several days upon cell culture conditions. The fabrication of substrates with adjacent antifouling and adhesion-promoting regions allows us to reach absolute spatial control in the positioning of neuroblastoma cells on the Teflon-AF films. This patterning approach of a technologically-relevant substrate can be of interest in tissue engineering and biosensing. [source]


    A New Approach to the Synthesis of N,N -Dialkyladenine Derivatives

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 29 2007
    M. José Alves
    Abstract N,N- Dialkyladenine derivatives were prepared by two different reaction sequences starting from 5-amino-4-cyanoformimidoylimidazoles. When these imidazoles were treated with dimethylformamide diethyl acetal, a 5-aminomethyleneamino-4-cyanoformimidoylimidazole was isolated and evolved to the N,N- dialkyladenine in the presence of a secondary alkylamine. The same purine structure was isolated when the 5-amino-4-cyanoformimidoylimidazole was first treated with a secondary amine to give a stable 4-amidino-5-aminoimidazole. The desired product was generated when the 4-amidino-5-aminoimidazole was combined with dimethylformamide diethyl acetal, at room temperature. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]


    A New Approach for Adipose Tissue Regeneration Based on Human Mesenchymal Stem Cells in Contact to Hydrogels,an In Vitro Study,

    ADVANCED ENGINEERING MATERIALS, Issue 10 2009
    Kirsten Peters
    In this study an approach for adipose tissue regeneration based on human mesenchymal stem cells and hydrogels as supporting matrix was evaluated. The gelatin-based hydrogels developed in this study were cytocompatible and stem cell adhesion onto hydrogel surfaces was higher as compared to tissue culture polystyrene. Furthermore, the adipogenic differentiation degree was increased. These results are promising for future applications of hydrogels in adipose tissue regeneration strategies. [source]


    Screening by NMR: A New Approach for the Study of Bioactive Natural Products?

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 7 2005
    The Example of Pleurotus ostreatus Hot Water Extract
    Abstract Direct NMR screening of natural products obtained from hot water extracts of medicinal species is accomplished through STD and tr-NOESY experiments on a crude mixture and a given protein receptor. It is shown, with use of a mushroom extract as model case, that this protocol may provide a fast and simple method, particularly useful in natural products chemistry, through which to detect the presence of ligands for a target receptor. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source]


    Gender and Biodiversity: A New Approach to Linking Environment and Development

    GEOGRAPHY COMPASS (ELECTRONIC), Issue 2 2007
    Janet Henshall Momsen
    The 1992 Convention on Biological Conservation and the International Treaty on Plant Genetic Resources for Food and Agriculture (1996) reflect the growing importance of biodiversity for environmental conservation and as a way of maintaining the genetic variety needed for plant breeding and providing new sources of medicines. More recently, agrobiodiversity has been seen as vital for food security in developing countries. This article considers the need to understand decision-making for biodiversity at the grassroots. To achieve this, gender roles, as influenced by gender divisions of labour in food production and the gendered use of different environmental spaces, have to be considered. Women's roles in seed selection and seed saving and use of wild plants for food and medicines play a major role in biodiversity conservation, but these roles are not unchanging and are increasingly influenced by global trade networks and geographical context. [source]


    New Approach Toward Fast Response Light-Emitting Electrochemical Cells Based on Neutral Iridium Complexes via Cation Transport

    ADVANCED FUNCTIONAL MATERIALS, Issue 5 2009
    Tae-Hyuk Kwon
    Abstract Here, a new method is presented to increase the turn-on time and stability of light-emitting electrochemical cells (LECs). To this end, a neutral iridium complex (5) containing a pendant Na+ ion that is generally known to have a faster mobility in the solid film than bulky anions is introduced, instead of the classic ionic transition metal complex (iTMC) with counter anion (7). Synthesis, photophysical and electrochemical studies of these complexes are reported. In the device configuration of ITO/5 or 7+PEO (polyethylene oxide) (100,110,nm)/Au, as the voltage increases, complex 5 emits red light at ,3.6,V while complex 7 appears at ,5.6,V, although their electrochemical and photophysical gap are similar. Furthermore, at constant voltage, ,3,V, the turn-on time of complex 5 was less than 0.5,min, which is a 60-fold faster turn-on time compared to the iTMC (7) with PF6,. These results are presumably due to the faster delivery of the Na+ ions to the electrode compared to PF6, ions. Also, the device lifetime of complex 5 exhibits a six-fold increase in stability and a three-fold shorter time to reach maximum brightness at constant bias compared to the device made with complex 7. [source]


    Governing Standards: The Rise of Standardization Processes in France and in the EU

    GOVERNANCE, Issue 1 2007
    OLIVIER BORRAZ
    The rise of standardization processes highlights two different paths toward a regulatory state. Within the EU, the New Approach serves as a model for co-regulation, and European standards have become instruments of supranational governance. In France, standardization is much more part of a renegotiation of the state's role and influence in a changing society. In both cases, standardization was undertaken with other motives; yet it evolved to answer the strains and constraints exerted upon regulatory processes in the two polities. As such, standards are a case for unintentionality in policy instruments. [source]


    Creating Securities Markets in Developing Countries: A New Approach for the Age of Automated Trading

    INTERNATIONAL FINANCE, Issue 2 2001
    Benn Steil
    The past decade has been one of enormous change in the securities trading industry. Automation of trading systems, led by the continental European exchanges and US ,electronic communications networks' (ECNs), has resulted in significant declines in trading costs, massive increases in turnover, internationalization of trading and settlement system operations, and major reforms in exchange governance. Yet the policy advice given to developing country governments looking to create or expand securitized finance in their markets has been largely unaffected by these developments. This is unfortunate, as developing countries now have the opportunity to leapfrog the evolving infrastructure of the mature markets and to define the global efficient frontier in trading technology, exchange governance, investor access and market structure regulation. This paper analyses the technological and economic forces driving change in the securities trading industry, and examines the implications for developing markets. [source]


    Advantageous 3D Ordering of ,-Conjugated Systems: A New Approach Towards Efficient Charge Transport in any Direction,

    ADVANCED MATERIALS, Issue 24 2007
    H. Pang
    A new organic semiconductor based on a benzobisthiazole core has been studied as a hole transport material in field effect transistors; remarkably, the material self-assembles in the solid state to give intermolecular short contacts in all three dimensions. [source]


    A New Approach to Pyrrolocoumarin Derivatives by Palladium-Catalyzed Reactions: Expedient Construction of Polycyclic Lamellarin Scaffold

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2009
    Lei Chen
    Abstract A new and efficient protocol for straightforward synthesis of chromeno[3,4- b]pyrrol-4(3H)-one derivatives by palladium-catalyzed sequential coupling/cyclization reactions has been developed. The key strategy relies on creation of pyrrole ring through palladium-catalyzed intramolecular hydroamination of related acetylenic aminocoumarins. The synthetic utility of the obtained chromeno[3,4- b]pyrrol-4(3H)-one product has been demonstrated by the expedient synthesis of polycyclic lamellarin scaffold in four steps. It provides a new entry to synthesis of potentially valuable lamellarin analogues. [source]


    Examination and Measurement of Halo Via Curvilinear Regression: A New Approach to Halo1

    JOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 2 2009
    Adrian Thomas
    Much disagreement and confusion has surrounded the nature of the relationship between halo and performance rating accuracy. Traditionally, the relationship has been assumed to be linear (Cooper, 1981), but Fisicaro (1988) proposed that the relationship between halo and performance rating accuracy is, instead, curvilinear. Using the halo index suggested by Balzer & Sulsky (1992), the results of the present study provided empirical evidence to support Fisicaro's proposal. Future research examining the relationship between halo and accuracy should consider the use of quadratic models, instead of linear ones. For the practitioner, this result implies that low rating dimension intercorrelations (negative halo) may lead to inaccuracy in ratings in much the same way as do high rating dimension intercorrelations (positive halo). [source]


    Study of the Nonresorptive Phenotype of Osteoclast-like Cells from Patients with Malignant Osteopetrosis: A New Approach to Investigating Pathogenesis

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 2 2000
    Adrienne M. Flanagan
    Abstract Osteopetrosis manifests as failure of osteoclastic bone resorption. The cause of the disease lies either in the hematopoietic lineage or in the bone marrow stromal microenvironment. It has not been possible to define the cell type involved in the various forms of the human disease because of the inability to form human osteoclasts in vitro. Using the recently described method for generating human osteoclasts from peripheral blood in coculture with rat osteoblastic UMR 106 cells, we demonstrate that a defect lies in the mature osteoclast-like cells in four cases of this disease. Control and osteopetrotic cocultures generated large numbers of osteoclast-like cells (calcitonin and vitronectin receptor positive, and F-actin ring,positive cells) with similar morphology. Bone resorption did not occur in three of the four osteopetrotic cultures. In case 1, in which bone resorption was identified, the area of resorption was negligible compared with the number of osteoclast-like cells in the culture and was detected only by scanning electron microscopy. In contrast, up to 20% of the bone surface in controls was resorbed. The normal and osteopetrotic osteoclast-like cells had a similar phenotype except that two of the osteopetrotic cases did not express CD44 and two expressed CD44 weakly, whereas CD44 was strongly expressed in the controls. This study shows that it is possible to reproduce in vitro the pathological features of human osteopetrosis, and the assay provides a means of acquiring a greater understanding of the pathogenesis of human osteopetrosis. (J Bone Miner Res 2000;15:352,360) [source]


    New Approach to Biphasic Waveforms for Internal Defibrillation:

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2000
    Fully Discharging Capacitors
    Internal Defibrillation with Fully Discharging Capacitors. Introduction: The use of two independent, fully discharging capacitors for each phase of a biphasic defibrillation waveform may lead to the design of a simpler, smaller, internal defibrillator. The goal of this study was to determine the optimal combination of capacitor sizes for such a waveform. Methods and Results: Eight full-discharge (95/95% tilt), biphasic waveforms produced by several combinations of phase-1 capacitors (30, 60, and 90 ,F) and phase-2 capacitors (1/3, 2/3, and 1.0 times the phase-1 capacitor) were tested and compared to a single-capacitor waveform (120 ,F, 65/65% tilt) in a pig ventricular fibrillation model (n = 12, 23 ± 2 kg). In the full-discharge waveforms, phase-2 peak voltage was equal to phase-1 peak voltage. Shocks were delivered between a right ventricular lead and a left pectoral can electrode. E50s and V50s were determined using a ten-step Bayesian process. Full-discharge waveforms with phase-2 capacitors of ,40 ,F had the same E50 (6.7 ± 1.7 J to 7.3 ± 3.9 J) as the single-capacitor truncated waveform (7.3 ± 3.7 J), whereas waveforms with phase-2 capacitors of ,60 ,F had an extremely high E50 (14.5 ± 10.8 J or greater, P < 0.05). Moreover, of the former set of energy-efficient waveforms, those with phase-1 capacitors of ,60 ,F additionally exhibited V50s that were equivalent to the V50 of the single-capacitor waveform (344 ± 65 V to 407 ± 50 V vs 339 ± 83 V). Conclusion: Defibrillation efficacy can be maintained in a full-discharge, two-capacitor waveform with the proper choice of capacitors. [source]


    Enamel Microabrasion: A New Approach

    JOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 2 2000
    THEODORE P. CROLL DDS
    ABSTRACT Enamel microabrasion is a proven method of removing superficial intrinsic enamel discoloration defects. The method is safe, easily performed, and causes no discomfort for the patient. A new commercially available microabrasion system has been introduced by Ultradent Products Inc. In addition, a new tooth isolation material is available, along with a visible light-activated in-office hydrogen peroxide solution. This article describes these new products and documents tooth-color correction for two young patients using this new tooth-color correction approach. CLINICAL SIGNIFICANCE Enamel microabrasion and vital bleaching can be used effectively to treat enamel dysmineralization and associated discoloration in children and adolescents. [source]


    Plant-Derived Vaccines: A New Approach to International Public Health

    JOURNAL OF FOOD SCIENCE, Issue 1 2004
    CHARLES J. ARNTZEN
    No abstract is available for this article. [source]


    Talairach-Based Parcellation of Neonatal Brain Magnetic Resonance Imaging Data: Validation of a New Approach

    JOURNAL OF NEUROIMAGING, Issue 4 2005
    Haissam Haidar PhD
    ABSTRACT Background and Purpose. Talairach-based parcellation (TP) of human brain magnetic resonance imaging (MRI) data has been used increasingly in clinical research to make regional measurements of brain structures in vivo. Recently, TP has been applied to pediatric research to elucidate the changes in regional brain volumes related to several neurological disorders. However, all freely available tools have been designed to parcellate adult brain MRI data. Parcellation of neonatal MRI data is very challenging owing to the lack of strong signal contrast, variability in signal intensity within tissues, and the small size and thus difficulty in identifying small structures used as landmarks for TP. Hence the authors designed and validated a new interactive tool to parcellate brain MRI data from newborns and young infants. Methods. The authors' tool was developed as part of a postprocessing pipeline, which includes registration of multichannel MR images, segmentation, and parcellation of the segmented data. The tool employs user-friendly interactive software to visualize and assign the anatomic landmarks required for parcellation, after which the planes and parcels are generated automatically by the algorithm. The authors then performed 3 sets of validation experiments to test the precision and reliability of their tool. Results. Validation experiments of intra-and interrater reliability on data obtained from newborn and 1-year-old children showed a very high sensitivity of >95% and specificity >99.9%. The authors also showed that rotating and reformatting the original MRI data results in a statistically significant difference in parcel volumes, demonstrating the importance of using a tool such as theirs that does not require realignment of the data prior to parcellation. Conclusions. To the authors' knowledge, the presented approach is the first TP method that has been developed and validated specifically for neonatal brain MRI data. Their approach would also be valuable for the analysis of brain MRI data from older children and adults. [source]


    Investigation of a New Approach to Measuring Contact Angles for Hydrophilic Impression Materials

    JOURNAL OF PROSTHODONTICS, Issue 2 2007
    Gerard Kugel DMD
    Purpose: The purpose of this investigation was to examine the initial water contact angles of seven unset impression materials using commercially available equipment, in an effort to determine whether polyether impression materials (Impregum) have lower contact angles and are, therefore, more hydrophilic than VPS impression materials. Materials and Methods: The hydrophilic properties of unset polyether and VPS impression materials were analyzed with respect to their water contact angle measurements using the commercially available Drop Shape Analysis System DSA 10. Twenty-five data points per second were collected via video analysis. There was no delay from start of measurement and data collection. Data was collected for approximately 12 s. Droplet size was determined on the thickness of canula. If the droplets became too small in volume, the water that evaporated during the measurement was large in comparison to the volume of the droplet. Therefore, 5 ,l was chosen as the lowest volume. Five trials were conducted per series for each featured material. Contact angles were calculated using the circle fitting method. Three tests using this technique were designed to control the variables of contact angle measurement with regard to time, the varying amount of fluid in contact with impression material during clinical use, and material thickness. Sample thickness of impression material was controlled by stripping the paste flat on a glass plate using a marking template to ensure a constant film thickness. Tests were conducted in a climatized room at 24°C ± 1°C. Deionized water was used as the fluid. The device was calibrated according to manufacturer's instruction for Young,Laplace fitting prior to the measurements. Results were analyzed using One-Way ANOVA, Tukey test, and t -test, as appropriate. Results: Comparing the fast setting impression materials by One-Way ANOVA and Tukey tests (p < .05) revealed the initial contact angles to range from 66.2 ± 1.5° to 127.5 ± 4.4°, of which the polyether material was the lowest after 45 s (66.2 ± 1.5°), 120 s (70.3 ± 2.8°), and 24 h (80.3 ± 1.0°) after start of the mix. The selected times represent the different stages of unset material, ranging from 45 s as the earliest practical data collection time to 24 h, at which a stone model would be poured. The polyether materials tested exhibited lower contact angles and, thus, significantly higher initial hydrophilicity than all measured VPS materials. Additionally, Impregum impression materials are more hydrophilic in the unset stage than in the set stage. VPS may show a stepwise development of hydrophilicity in the set stage that was not observed in the unset stage. Conclusions: The polyether impression materials tested were significantly more hydrophilic before, during, and after setting than that of VPS impression materials. Regardless of the amount of water in contact with the impression material, the polyether impression materials showed a significantly higher hydrophilicity in the unset stage than the VPS materials. The initial contact angle was not dependent on the thickness of the material. All parameters, including variation of time, volume of water droplet, and thickness of material, resulted in different absolute contact angles, but did not lead to a dramatic change in the ranking of the materials with regard to their hydrophilic behavior. [source]


    Rifaximin: A New Approach to the Treatment of Travelers'Diarrhea

    JOURNAL OF TRAVEL MEDICINE, Issue 2001
    Charles D. Ericsson
    No abstract is available for this article. [source]


    New Approach in Modeling of Metallocene-Catalyzed Olefin Polymerization Using Artificial Neural Networks

    MACROMOLECULAR THEORY AND SIMULATIONS, Issue 3 2009
    Mostafa Ahmadi
    Abstract A new approach for the estimation of kinetic rate constants in olefin polymerization using metallocene catalysts is presented. The polymerization rate has been modeled using the method of moments. An ANN has been used and trained to behave like the mathematical model developed before, so that it gets polymerization rate at different reaction times and predicts reaction rate constants. The network was trained using modeling results in desired operational window. The polymerization rates were normalized to make the network work independent of operational conditions. The model has also been applied to real polymerization rate data and the predictions were satisfactory. This model is specially useful in comparing different new metallocene catalysts. [source]


    A New Approach to the Deposition of Elemental Boron and Boron-Based Coatings by Pulsed Magnetron Sputtering of Loosely Packed Boron Powder Targets

    PLASMA PROCESSES AND POLYMERS, Issue S1 2007
    Martynas Audronis
    Abstract Large numbers of potential application areas for elemental boron and boron-based thin film materials make this subject area a focus of significant scientific and industrial interest. Applications include thermoelectric energy conversion devices, biomedical implants, metalworking tools and automotive components. Boron is however also recognised widely to be a difficult-to-deposit material. Therefore, a new technique to deposit boron (and other boron-based materials) by pulsed magnetron sputtering of loosely packed powder targets has been proposed. Among the benefits of this approach are: improved stability of the deposition process, increased speed and flexibility of target preparation, enhanced time- and cost-effectiveness and the ability to control readily the target and hence the chemical composition of the coating. [source]