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Different Devices (different + device)

Distribution by Scientific Domains

Medical Sciences	44%
Chemistry	22%

Selected Abstracts

A Comparative Study on PSD Models for Chromite Ores Comminuted by Different Devices

PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 1-2 2009
Adem Ta, demir
Abstract The objective of this study was to characterize the particle size distributions (PSDs) of chromite ores comminuted by different devices, i.e., subjected to different breakage modes and to compare the performances of the PSD functions selected. Different PSDs were obtained for five different mineralogical samples of chromite ores by jaw, cone and hammer crushing and ball mill grinding. The PSDs of the products were characterized to find the most suitable model by Gates,Gaudin,Schuhmann (GGS) and Rosin,Rammler (RR) functions. It was found that the PSDs of all chromite types in single-pass devices, i.e., jaw and cone crushing were better described by the GGS model than RR model. The RR model gave the best results for all ore sample PSDs generated by retention type systems, i.e., hammer crushing and ball mill grinding. Both distribution functions gave higher R2 values as the size distribution became uniform. The results of piecewise regression were found very useful to improve the performance of GGS distribution in terms of correlation coefficients for samples from a hammer crusher and ball mill. [source]

A Comparison of GlideScope Video Laryngoscopy Versus Direct Laryngoscopy Intubation in the Emergency Department

ACADEMIC EMERGENCY MEDICINE, Issue 9 2009
Timothy F. Platts-Mills MD
Abstract Objectives:, The first-attempt success rate of intubation was compared using GlideScope video laryngoscopy and direct laryngoscopy in an emergency department (ED). Methods:, A prospective observational study was conducted of adult patients undergoing intubation in the ED of a Level 1 trauma center with an emergency medicine residency program. Patients were consecutively enrolled between August 2006 and February 2008. Data collected included indication for intubation, patient characteristics, device used, initial oxygen saturation, and resident postgraduate year. The primary outcome measure was success with first attempt. Secondary outcome measures included time to successful intubation, intubation failure, and lowest oxygen saturation levels. An attempt was defined as the introduction of the laryngoscope into the mouth. Failure was defined as an esophageal intubation, changing to a different device or physician, or inability to place the endotracheal tube after three attempts. Results:, A total of 280 patients were enrolled, of whom video laryngoscopy was used for the initial intubation attempt in 63 (22%) and direct laryngoscopy was used in 217 (78%). Reasons for intubation included altered mental status (64%), respiratory distress (47%), facial trauma (9%), and immobilization for imaging (9%). Overall, 233 (83%) intubations were successful on the first attempt, 26 (9%) failures occurred, and one patient received a cricothyrotomy. The first-attempt success rate was 51 of 63 (81%, 95% confidence interval [CI] = 70% to 89%) for video laryngoscopy versus 182 of 217 (84%, 95% CI = 79% to 88%) for direct laryngoscopy (p = 0.59). Median time to successful intubation was 42 seconds (range, 13 to 350 seconds) for video laryngoscopy versus 30 seconds (range, 11 to 600 seconds) for direct laryngoscopy (p < 0.01). Conclusions:, Rates of successful intubation on first attempt were not significantly different between video and direct laryngoscopy. However, intubation using video laryngoscopy required significantly more time to complete. [source]

Implementation of the symmetric doped double-gate MOSFET model in Verilog-A for circuit simulation

INTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 2 2010
Joaquín Alvarado
Abstract Recently we developed a model for symmetric double-gate MOSFETs (SDDGM) that, for the first time, considers the doping concentration in the Si film in the complete range from 1×1014 to 3×1018,cm,3. The model covers a wide range of technological parameters and includes short channel effects. It was validated for different devices using data from simulations, as well as measured in real devices. In this paper, we present the implementation in Verilog-A code of this model, which allows its introduction in commercial simulators. The Verilog-A implementation was optimized to achieve reduction in computational time, as well as good accuracy. Results are compared with data from 2D simulations, showing a very good agreement in all transistor operation regions. Copyright © 2009 John Wiley & Sons, Ltd. [source]

The Amplatzer Duct Occluder II: A New Device for Percutaneous Ductus Arteriosus Closure

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 6 2009
ZAKHIA SALIBA M.D.
Objective: Study the new Amplatzer Duct Occluder II (ADO II). Limitations were encountered with the preexisting devices in nonconical ducts, large ducts, or in small infants. These include failure, residual shunts, protrusion, migration, and vascular damage. Methods: Between June 2008 and March 2009, 20 consecutive patients were enrolled. In cases where different devices were applicable, we favored the use of the ADO II to maximize our experience with this device and prove its superiority. No coils were required in these 20 patients. Results: There were 15 females and 5 males (median age 2 years). ADO II group (n = 16): Immediate complete closure in 75% of the patients, rising to 93.7% at 24 hours. A residual shunt persisted at 3 months in one child. Aortic narrowing from device protrusion was noted in two type E ducts, without any significant gradient, however. ADO I group (n = 4): In two adolescents and in one adult patient, the duct was successfully closed. In a 2-year-old patient with a 6.6 mm type B duct, the ADO I totally obstructed the aortic flow and was retrieved before releasing. The child was sent for surgery. Conclusion: Even though we did not compare the ADO II to other devices, we feel that it has the capacity to substitute most of the coils, and some of the original ADO I indications. Arterial access was sufficient in most patients, but venous delivery is advised in small infants with large or long ducts, to avoid aortic protrusion and residual shunts. [source]

A Comparative Study on PSD Models for Chromite Ores Comminuted by Different Devices

Single-crystal neutron diffraction investigation on crystals belonging to the langasite family: a comparative study

ACTA CRYSTALLOGRAPHICA SECTION B, Issue 5 2010
R. Chitra
Crystals of the langasite family are of interest as they are piezoelectric in different devices. The properties of these classes of crystals can be modified within certain limits by isomorphous substitution. Single-crystal neutron diffraction studies were carried out for LGT (La3Ga5.5Ta0.5O14), LGST (La3Ga5.25Ta0.25Si0.5O14) and LGZrT (La3Ga5.25Ta0.25Zr0.5O14) as the neutron study gives a better average picture of the crystal properties over a macroscopic region of the grown crystal. The effect of small substitutions at various sites on the piezoelectric properties of the crystal was studied. [source]

Adjunctive use of the Rinspiration system for fluidic thrombectomy during primary angioplasty: The Rinspiration international registry,

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 2 2008
Marco De Carlo MD
Abstract Background: Atherothrombotic embolization during primary percutaneous coronary intervention (PCI) induces microvascular obstruction and reduces myocardial tissue reperfusion. A variety of thrombectomy devices have been evaluated as an adjunct to primary PCI in patients with ST-elevation myocardial infarction (STEMI) to reduce distal embolization. Results have been inconsistent and difficult to predict. The aim of this study was to investigate the safety and efficacy of an innovative thrombectomy device, the Rinspiration System, which simultaneously "rinses" the vessel with turbulent flow and aspirates thrombus. Methods: We prospectively enrolled 109 patients at six academic institutions in three countries referred for primary or rescue PCI for STEMI presenting within 12 hr of symptom onset. The primary endpoint was ,50% ST-segment elevation resolution (STR) measured 60 min after PCI by continuous elctrocardiographic recording, Secondary end points included STR > 70% at 60 min, final TIMI flow, myocardial blush score, and 30-day major adverse cardiac events (MACE). Results: Mean symptom-to-PCI time was 4.7 ± 2.7 hr. Rinspiration was successfully delivered in 98% of cases. Final TIMI three flow was achieved in 89% of patients and myocardial blush ,2 in 78%. Rates of STR , 50% and >70% at 60 min were 97 and 80%, respectively. No device-related complications were observed. Thirty-day MACE rate was 4.6%. Conclusions: This international multicenter registry demonstrates that the adjunctive use of Rinspiration during primary PCI is safe and feasible. The excellent STR data compare favorably with results of previous trials using different devices for thrombus management, indicating a potential clinical benefit. © 2008 Wiley-Liss, Inc. [source]

Comparison of anterior chamber depth measurements taken with the Pentacam, Orbscan IIz and IOLMaster in myopic and emmetropic eyes

ACTA OPHTHALMOLOGICA, Issue 4 2009
Canan Asli Utine
Abstract. Purpose:, This study determined to assess the degree of agreement between anterior chamber depth (ACD) measurements obtained using three different devices and to analyse the relationship between ACD and spherical equivalent (SE) refraction. Methods:, In this cross-sectional study, 42 eyes of 42 patients with a mean SE of , 4.69 ± 4.61 D (range 0.00 D to , 14.88 D) were analysed. Measurements of ACD between the corneal epithelium and the anterior surface of the crystalline lens, obtained using the Pentacam, Orbscan IIz and IOLMaster, were compared. The relationships between SE and ACD measurements obtained with different devices were also investigated. The results were analysed using Bland,Altman analyses, single-sample t -test and Pearson's correlation test. Results:, Orbscan ACD measurements were an average of 0.05 mm less than Pentacam measurements (p = 0.01). IOLMaster measurements were an average of 0.06 mm less than Orbscan measurements (p < 0.001). None of the ACD values measured by any of the devices were correlated with increasing SE (p > 0.05 for all). There was a weak positive correlation between SE and the difference in ACD measurements with Pentacam and Orbscan (p = 0.04); however, the differences between Pentacam and IOLMaster ACD measurements and Orbscan and IOLMaster ACD measurements seemed to be independent of SE (p = 0.17 and p = 0.54, respectively). Conclusions:, The ACD in clinically normal eyes is measured differently by various non-ultrasonic devices. However, the observed mean error between these modalities is too small to create any noticeable difference in refractive outcome. No significant relationship was found between SE and ACD measurements obtained by Pentacam, Orbscan or IOLMaster. [source]

Overcoming Kinetic Limitations of Electron Injection in the Dye Solar Cell via Coadsorption and FRET

CHEMPHYSCHEM, Issue 5 2008
Conrad Siegers
Abstract A new, extremely simple concept for the use of energy transfer as a means to the enhancement of light absorption and current generation in the dye solar cell (DSC) is presented. This model study is based upon a carboxy-functionalized 4-aminonaphthalimide dye (carboxy-fluorol) as donor, and (NBu4)2[Ru(dcbpy)2(NCS)2] (N719) as acceptor chromophores. A set of three different devices is assembled containing either exclusively carboxy-fluorol or N719, or a mixture of both. This set of transparent devices is characterized via IV-measurements under AM1.5G and monochromatic illumination and their light-harvesting and external quantum efficiencies (LHE and EQE, respectively) are determined as well. It is shown that the device containing only the donor chromophore has a marginal power conversion efficiency, thus indicating that carboxy-fluorol is a poor sensitizer for the DSC. Cyclovoltametric measurements show that the poor sensitization ability arises from the kinetic inhibition of electron injection into the TiO2 conduction band. Comparing the spectral properties of the DSCs assembled presently, however, demonstrates that light absorbed by carboxy-fluorol is almost quantitatively contributing to the photocurrent if N719 is present as an additional sensitizer. In this case, N719 acts as a catalyst for the sensitization of TiO2 by carboxy-fluorol in addition to being a photosensitizer. Evaluation of the maximum output power under blue illumination shows that the introduction of an energy-donor moiety via coadsorption, leads to a significant increase in the monochromatic maximum output power. This result demonstrates that energy transfer between coadsorbed chromophores could be useful for the generation of current in dye-sensitized solar cells. [source]