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Abstract: Vibrothermography, or sonic IR, is a nondestructive evaluation technique used to find surface and near surface defects—such as cracks and delaminations—through observations of vibration-induced heat generation. This method has significant interest as an industrial inspection method, however, a lack of understanding of the fundamental physics governing the heat generation process has limited its application despite extensive theoretical, numerical simulation, and experimental work. Significant theoretical and numerical simulation work has been performed, but has yet to be rigorously verified experimentally. This paper presents experimental verification of the sources of heat generation in vibrothermography; specifically friction, plasticity, and viscoelasticity. Specific experimental evidence is presented that verifies each of these heat-generating mechanisms. [Copyright &y& Elsevier]

BACKGROUND Our goal is to improve student learning in foundation engineering courses. These courses are prerequisite to many higher-level courses and are comprised of critically needed concepts and skills. PURPOSE(HYPOTHESIS) We hypothesize that learning is improved by providing rapid feedback to students on their understanding of key concepts and skills. Such feedback also provides students with insight into their strategies for learning. DESIGN/METHOD In two consecutive years, we conducted this study in two sections of a lower-level engineering mechanics course, Statics. One author taught both sections and a crossover design of experiment was used. In a crossover design, one section was randomly chosen to receive feedback with handheld computers (the "treatment" group) while the other received the "control," which was either a feedback system using flashcards (in year 1) or no feedback (year 2). After a certain period, the two sections swapped the treatment and control Student performance on a quiz at the end of each treatment period provided the data for comparison using an analysis of variance model with covariates. RESULTS Findings from year 1 showed that there was no significant difference using either rapid-feedback method. In year 2 we found a significant and positive effect when students received feedback. CONCLUSIONS This is a noteworthy finding, albeit within the constraints of the environment in which we conducted the study, that provides more evidence for the value of rapid feedback and the currently popular "clickers" that many professors are employing to promote classroom interaction and student engagement. [ABSTRACT FROM AUTHOR]

Abstract: In fluidization processes, the optimal contacting regime is dictated by the physical or chemical process in question, and can vary significantly from application to application. Even within the specified regime, it is often necessary to place constraints on the hydrodynamic behavior in order to meet operational requirements. While the ability to do this is very important, there is a lack in current technologies'' ability to identify the operational state via direct measurement. This work adopts a local transient approach towards addressing this problem. In order to study the local fluid bed dynamics, needle-type capacitance probes were employed to gather local transient solids fraction data in a bench-scale bubbling bed. The time-series were then subject to analysis in order to extract various signal invariants. The parametric effects of axial measurement location, superficial gas velocity, and mean particle size were examined in order to identify favorable heuristic trends in the signal invariants with respect to global parameters governing fluidization quality (i.e., superficial gas velocity and mean particle size). This work demonstrates how these invariants then constitute the basis for a novel regime map based monitoring scheme for quality of fluidization with potential application to feedback control. [Copyright &y& Elsevier]

We have developed an experiment to study the propagation of laboratory-synthesized fatigue cracks under various controlled conditions during Sonic IR inspection. The experiment provides for good repeatability in testing. The parameters of interest include the initial crack length, load history (stress intensity and load ratio) during crack generation, geometry of the crack, material and also the various conditions involving the ultrasonic excitation source. In general, we find that under typical sonic IR inspection conditions, the initial crack will propagate under sonic IR testing. The crack growth after each inspection event varies and exhibits a distribution in length of propagation. The results show that the average crack propagation decreases with increasing stress intensity factor, and we test two hypotheses about the cause of this. Furthermore, we find that crack propagation is affected by the initial crack length. [ABSTRACT FROM AUTHOR]

Ethylene ionomers, such as Surlyn® from DuPont, have been the premium sealant materials for packaging applications due to their excellent seal strength and process robustness. The ethylene ionomers exhibit their unique property characteristics because they form a network morphology. In this article new ethylene ionomers will be discussed. Their versatile compositions and the unique morphology will be described together with enhanced gas permeability properties. [ABSTRACT FROM AUTHOR]

The article examines Chinese American families by focusing on the life of Chinese scholar Li Yourong, who was stranded in the U.S., and her daughter Yiling, whom she was forced to leave behind in China. It is based largely on oral histories and unpublished memoirs. The story is also unusual because traditional Chinese families did not spend too much of their resources on educating girls since daughters left the family home and were not responsible for supporting their parents in their old age.

Abstract: Large-scale fluidized beds for commercial processes commonly require heat transfer surfaces. Design then demands that heat transfer coefficients be specified. Empirical correlations are unable to cover the wide range of variables and conditions encountered. Mechanistic models are more reliable, but must be chosen carefully. For bubbling beds, the packet model approach gives reasonable predictions for the convective component of transfer, but further work is required to provide reliable estimates of two required time constants, dependent on the hydrodynamics. For industrial-scale circulating beds, a mechanistic model that incorporates the key factors influencing heat transfer, assumes fully developed transfer, and utilizes results from large-scale units is recommended. [Copyright &y& Elsevier]

Background:Inflammation contributes to morbidity following on-pump cardiac surgery. Complement activation during cardiopulmonary bypass has been associated with the postoperative bleeding and tissue injury. This study examines the pharmacology and impact on blood loss of complement C5 suppression with pexelizumab in patients undergoing cardiac surgery with cardiopulmonary bypass.Methods:Pexelizumab, a humanized monoclonal antibody single-chain fragment that binds to the human C5 complement component, was studied in a Phase II multicentered clinical trial. CABG (n= 800) and CABG with concomitant valve surgery (n= 114) patients were evaluated. Patients were randomized to either: pexelizumab bolus (2.0 mg/kg)+ placebo infusion; pexelizumab bolus (2.0 mg/kg)+ pexelizumab infusion (0.05 mg/kg/hour for 24 hours); or placebo bolus+ placebo infusion. Pharmacology, chest tube drainage, and transfusion requirements were assessed.Results:Mean maximum pexelizumab serum concentration was similar for bolus and bolus+ infusion-treated patients. Complement-dependent serum hemolytic activity was completely suppressed within 1 hour following pexelizumab bolus, however, suppression was maintained for a longer duration in the bolus+ infusion compared to the bolus-only treated patients. A reduction in chest tube drainage was observed for all pexelizumab-treated patients, although transfusion of blood products was similar across all study groups.Conclusion:Pexelizumab administration inhibits complement-dependent hemolytic activity and is associated with a reduction in postoperative chest tube drainage in patients undergoing cardiac surgery requiring cardiopulmonary bypass. Further, clinical studies are needed to assess the value of complement attenuation in this setting.(J Card Surg 2005;20:35-41) [ABSTRACT FROM AUTHOR]

Relates the story of Calvin H. Chen, a Chinese physician and one of the so-called stranded scholars from China that stayed in the U.S. Description of the life and education of Chen in China; Decision of Chen to leave China and pursue postgraduate medical education in the U.S. following the end of the Second World War; Medical career of Chen in the U.S.; Impact of Chen's dilemmas over nationality, culture and heritage on his personal life and health.

Illustrates the significance of surface contact for multiphase heat transfer with examples from diverse systems, heat transfer in fluidized beds and dropwise condensation. Factors that affect basic mechanisms of transport between the multiphase medium and a submerged surface; Applications in which heat transfer between multiphase media and solid surfaces are encountered; Description of fluidized bed.

There currently exists a great interest in integrating technology into the engineering curriculum. The Southeastern University and College Coalition for Engineering Education (SUCCEED) has identified this topic to be one of four "focus areas" for the coalition, and is committed to supporting the effective use of technology in enhancing the learning and teaching environment. We report here the results of a survey of engineering faculty at the coalition universities to identify the training needs and present levels of experience with various technologies. The most surprising finding is that, despite the wide differences in the Coalition's colleges of engineering, the survey results are similar for all campuses. This implies that the results may be widely applicable to other universities. Generally, we found that the faculty's interest in receiving training in a specific technology is highly correlated with a low skill level for that topic, as expected. Of the ten potential workshop topics, those in highest demand include: • presenting lectures or demonstrations from a computer • creating, editing and incorporating multimedia into course materials • creating Web pages for a course • developing multimedia courseware • developing a course delivered entirely via the World Wide Web • developing Java applets to enhance courses • holding electronic help-sessions. [ABSTRACT FROM AUTHOR]

Aims: We have investigated the short term effects of fluorescein angiography on the blue-yellow, red-green, and luminance contrast senstivity of patients with early age-related macular degeneration (ARMD). Methods: Nine ARMD patients with no exudative complications and a visual acuity of 20/60 or better in the tested eye were selected. Cardinal colour directions for the isolation of the red-green, blue-yellow and achromatic (luminance) visual mechanisms were determined for each patient. Contrast sensitivity was measured in each cardinal colour direction immediately before and 20 mm after standard 20-flash fluorescein angiography. Results: A significant, albeit mild, reduction for blue-yellow contrast sensitivity following angiography was observed (ANOVA, α=0.05). Fluorescein angiographic exposure had no significant effect on red-green or luminance contrast sensitivity. Conclusion: Our results show that fluorescein angiography causes at least a short term deficit selective to blue-yellow contrast sensitivity in our patient group. [ABSTRACT FROM AUTHOR]

Important applications of fast fluidized beds include reactors where liquid feed is sprayed into the co-current flow of solid particles and gas. When the gas and the solid particles are superheated relative to the saturation temperature of the liquid, the liquid drops evaporate at a rate governed by interfacial heat and mass transfer. This article describes an experimental method to determine the rate of liquid evaporation in such three-phase systems. Analogous experiments were carried out with liquid nitrogen evaporating in superheated beds of sand particles and air. [ABSTRACT FROM PUBLISHER]

Examines the application of fast-track pathway techniques for improving outcomes following coronary artery bypass graft-surgery in patients with depressed left ventricular function in comparison with patients with normal ventricular function. Preoperative conditions; Operative features; Applicability to high risk patients.

Our radiant two-phase flow reactor presents several new possibilities for high-temperature reactivity studies. Most importantly, the thermal histories of the suspension and entrainment gas can be independently regulated over wide ranges. At low suspension loadings, outlet temperatures can differ by hundreds of degrees and gas temperatures are low enough to inhibit hydrocarbon cracking chemistry, so primary products are quenched as soon as they are expelled. With coal suspensions, tars were generated with the highest H/C ratio and lowest proton aromaticity ever reported. Alternatively, particles and gas can be heated at similar rates to promote secondary chemistry by increasing particle loading. Simply by regulating the furnace temperature, arbitrary extents of conversion of coal tar into soot were observed for fixed total mass loss. Under both circumstances heat fluxes are comparable to those in large furnaces, so relevant heating rates and reaction times are accessible. Suspensions remain optically thin even for the highest loadings of technological interest because they are only 1 cm wide. Consequently, the macroscopic behavior remains firmly connected to single-particle phenomena. Mass and elemental closures are rarely breached by more than 5% in individual runs, so interpretations are not subject to inordinate scatter in the data. The reactor is also well suited for combustion studies, as demonstrated by extents of carbon and nitrogen burnout from 50% to 100% for various gas-stream oxygen levels. [ABSTRACT FROM AUTHOR]

Editorial. Comments on an article reporting a prospective survey of patients undergoing surgical resection for lung cancer, published in the July 2002 issue of 'Chest.' Comparison of functional health status and quality of life using the Short-Form Health Survey; Probability of survival with regards to preoperative risk factors.

Abstract: Objective: The objective of this study was to delineate the difference in the phenotype of diabetic retinopathy (DR) in Latinos versus Blacks using characteristics shown on fundus photography (FP) and fluorescein angiography (FA). Research Design and Methods: This was a retrospective chart review of 203 adult Black and Latino diabetic patients from the King–Drew Medical Center eye clinic from January 1998 to March 2005. Systemic risk factors such as HbA1c and kidney function data were collected. FP and FA were analyzed and graded according to Early Treatment of Diabetic Retinopathy Study criteria. Statistical analysis was performed to determine whether a given lesion type was more characteristic of a particular racial group. Results: Gender, age, median microalbumin-to-creatinine ratio (ACR), and average HbA1c values were not significantly different between the groups. The presence of clinically significant macular edema (CSME), focal or diffuse, was very high in both groups (44% in Latinos and 46% in Blacks), and the overall DR grades were similar. However, upon individual lesion analysis, the Latinos were noted to have more prevalent intraretinal hemorrhages involving a greater area of the retina (P=.046). Conclusions: Although Latinos and Blacks of comparable age and glycemic control are equally at risk for CSME and proliferative retinopathy, Latinos may be at greater risk for a specific phenotype of DR characterized by extravasation of intraretinal hemorrhages, which is associated with poor prognosis. Further prospective studies may uncover racial differences that may have implications for prognosis and therapy. [Copyright &y& Elsevier]

Describes the movement of liquid drops on a surface with radial surface tension gradient. Growth of water droplets by coalescence; Exhibition of random motion from merging droplets; Comparison of speed between small drops and Marangoni flow.

Inception of bubble nucleation in falling films of binary mixtures were determined experimentally. The liquid films were distributed over the external surface of a vertical evaporator tube with OD of 38  mm and heated length of 3 m. Local wall superheats and heat fluxes were measured at the point of bubble nucleation for mixtures of glycerol and water, at absolute pressures varying from 25 to 434 mmHg. Film Reynolds numbers ranged from 82 to 1,800. The experimental results showed increasing wall superheat for boiling inception with decreasing absolute pressure, decreasing flow rate, and increasing concentration of the less volatile component (glycerol). [ABSTRACT FROM PUBLISHER]

The conventional two-step oxidation-esterification process has many defects due to its time-wasting, energy-consuming and quality-damping. To improve this, we developed a novel pseudo-single-step process (PSSP). In brief, to starch 400 g, 600 mL of sodium hypochlorite (0.7 M) (1.8% of starch) was added, pH adjusted to 8.0 and left to react for 1 h, then 1% acetic anhydride was added, pH adjusted to 8.0 and left to react for 3 h. The finished oxidized-esterified Cassava starch (COAEC) exhibited peak-, trough-, breakdown-, final- and setback viscosities as 3,507 ± 22 cp, 1,742 ± 33 cp, 1,765 ± 44 cp, 2,642 ± 34 cp and 900 ± 7 cp. FTIR identified the formation of carbonyl and carboxyl content. While X-ray diffractometry and differential scanning calorimetry further confirmed the destruction of microcrystalline structure. Sensory evaluation indicated COAEC had a score 5.3-5.7 compared to 4.9-5.2 of the native Cassava starch (score 7.0 = like extremely). Practical Applications Pseudo-single step oxidation-esterification process has successfully modified the Cassava starch (COAEC)., COAEC exhibits promisingly improved physico-chemical and sensory properties., COAEC meets the requirement for manufacturing the oriental special snacks and cold dishes. [ABSTRACT FROM AUTHOR]

Purpose. To describe the histopathological features of vitreous samples obtained after vitrectomy surgery from diabetic and nondiabetic patients. Methods. Vitreous specimens from 137 patients who underwent vitrectomy for different clinical conditions were analysed. All samples were centrifuged and each resulting pellet was fixed and processed as part of routine paraffin section histopathology. The histopathological features were categorized in a semiquantitative fashion. The samples from diabetic and nondiabetic patients were compared. Results. The 125 included patients (58 diabetic, 60% males) were aged 64.2±13.9 years. The presence of hemorrhage, inflammatory cells, and histiocytes was significantly higher in the diabetic group (P<0.001, P=0.028, and P=0.016, resp.), showing more vessels (P<0.001) and ghost vessels (P=0.049). The presence of inflammatory cells was the feature with the highest sensitivity for detecting diabetes mellitus (98%) and also the highest negative predictive value (89%). In the multivariate analysis, three variables emerged as independent significant predictors of diabetes in vitrectomy samples: hemorrhage, endothelial-lined vessels, and age (P<0.001, P<0.001, and P=0.019, resp.). Conclusions. Different histopathological features can be found in vitreous samples from diabetic patients. Analysis of vitrectomy samples may serve as a tool for diabetes management. [ABSTRACT FROM AUTHOR]

The objective of this work is to establish methods for storage of thermal energy using encapsulated phase change materials (EPCMs) at temperatures up to 440 °C applicable in concentrating solar plants (CSPs), in which heat transfer fluid (HTF) from the solar collector would pass through the storage system embedded with EPCM capsules. NaNO 3 , having latent heat of 176 kJ/kg at 308 °C, is selected as the storage medium. Stainless steel capsules containing NaNO 3 are fabricated and installed in a pilot-scale thermal energy storage (TES) system for performance tests. Compressed air is used as heat transfer fluid in the current tests. The test section (T/S) with EPCM capsules successfully demonstrate the ability to transfer thermal energy to and from a transport fluid, achieving energy storage and retrieval in multiple charging and discharging cycles. In a given cycle where capsule temperatures varied from ∼250 °C to ∼386 °C, the EPCM is found to store significant energy per unit mass (∼211 kJ/kg of capsule), with the phase change material (PCM) NaNO 3 accounting for ∼95% of the total energy stored in the capsules. The latent heat of the NaNO 3 contributes to ∼42% of the energy stored in the capsules. It is expected that the storage density of the EPCM would be even greater for plant size TES systems with larger size capsules, without the penalties associated with the limited scale used here. A mathematical model has been developed for the test section with EPCM capsules and its predictions are found to agree with experimental measurements within 7% discrepancy in stored energy. The dynamic performance of charging and discharging rates are also well predicted by the model, giving confidence for engineering design capabilities in future applications using EPCMs for thermal energy storage. [ABSTRACT FROM AUTHOR]

Investigations of the relationships between contexts in which learning occurs and students’ behaviours, cognitions and motivations may further our understanding of how instruction is related to students’ development as self-regulated learners. In this study, student self-regulated learning strategies in problem-based learning and project-based learning environments were examined to determine whether student self-regulation outcomes differed depending on the instructional design. Quantitative results showed that student motivations and behaviours were not statistically different in the two settings. Differences in cognitions associated with self-regulated learning were, however, observed in the two settings, with students in the project-based environments reporting higher levels of elaboration, critical thinking and metacognition. In addition, students in the project-based courses reported higher perceived autonomy support, or the degree to which they perceived their instructors provided them with supportive opportunities to act and think independently compared to students in the problem-based courses. These findings indicate that different non-traditional student-centred learning environments may support different outcomes related to self-regulated learning. [ABSTRACT FROM AUTHOR]

Abstract: The primary objective of this study is to develop encapsulated phase change materials (EPCMs) capable of storing thermal energy at temperatures above 750 °C. EPCM with magnesium chloride as phase change material (PCM) are considered here for application in concentrated solar power (CSP) systems. MgCl2 is an effective storage medium because of its high melting temperature, 714 °C, and high latent heat of fusion, 454 kJ/kg. A specialized calorimeter with requisite size and high temperature capability is designed and built to prove the storage capability of MgCl2 EPCM. The calorimeter is also used to determine heat capacities for MgCl2 in both liquid and solid states as well as its latent heat of fusion. Calorimetric tests for the thermal storage capacities of three MgCl2 EPCM samples show excellent agreement with published data. Based on the measured properties, the latent heat of phase change can contribute about 84% of the storage capacity of MgCl2 PCM for a 100 °C temperature swing bracketing the salt''s melting point. Repeated thermal-cycles show sustained performance of MgCl2 EPCM capsules with no discernible diminishment in storage capacity. [Copyright &y& Elsevier]

Abstract: The objective of this research was to develop encapsulated phase change materials (EPCMs) that can store thermal energy at temperatures up to 450°C, suitable for applications in concentrating solar power systems. From initial explorations of candidate media, the two salts (PCMs) NaNO3 and eutectic NaCl–MgCl2 were selected for further development as storage media with phase change. A specialized calorimeter with requisite size and temperature capability was designed and built to obtain enthalpy values of the PCMs at temperatures below and above their melting points. The latent heats of phase change can contribute 57% and 75% to storage capacity of the NaNO3 and NaCl–MgCl2 media, respectively, for a 100°C temperature swing bracketing the salts’ melting points. After calibration, this calorimeter was then used to determine the actual energy storage capacity achieved by capsules of EPCMs of various dimensions. The calorimeter tests proved that the salts and the encapsulation methods chosen here can store thermal energy effectively while taking advantage of the latent heat of phase change. Repeated thermal-cycles showed sustained performance of the EPCMs, with no discernible diminishment in storage capacity. [Copyright &y& Elsevier]

Context Inflammation and ischemia-reperfusion injury during coronary artery bypass graft (CABG) surgery requiring cardiopulmonary bypass are associated with postoperative myocardial infarction (MI) and mortality. Objective To determine the efficacy and safety of pexelizumab, a C5 complement inhibitor, in reducing perioperative MI and mortality in CABG surgery. Design, Setting, and Participants A randomized, double-blind, placebo-controlled trial, including 3099 patients (≥ 18 years) undergoing CABG surgery with or without valve surgery at 205 hospitals in North America and Western Europe from January 2002 to February 2003. Interventions Patients were randomly assigned to receive intravenous pexelizumab (2.0 mg/kg bolus plus 0.05 mg/kg per hour for 24 hours; n = 1553) or placebo (n = 1546) 10 minutes before undergoing the procedure. Main Outcome Measures The primary composite end point was the incidence of death or MI within 30 days of randomization in those undergoing CABG surgery only (n = 2746). Secondary analyses included the intent-to-treat analyses of death or MI composite at days 4 and 30 in all 3099 study patients. Results After 30 days, 134 (9.8%) of 1373 of patients receiving pexelizumab vs 161 (11.8%) of 1359 of patients receiving placebo (relative risk, 0.82; 95% confidence interval, 0.66-1.02; P = .07) died or experienced MI in the CABG surgery only population. In the intent-to-treat analyses, 178 (11.5%) of 1547 patients receiving pexelizumab vs 215 (14.0%) of 1535 receiving placebo died or experienced MI (relative risk, 0.82; 95% confidence interval, 0.68-0.99; P = .03). The trial was not powered to detect a reduction in mortality alone. Conclusions Compared with placebo, pexelizumab was not associated with a significant reduction in the risk of the composite end point of death or MI in 2746 patients who had undergone CABG surgery only but was associated with a statistically significant risk reduction 30 days after the procedure among all 30... [ABSTRACT FROM AUTHOR]

All engineering students at Rowan University are required to take the eight-semester Engineering Clinic sequence wherein multidisciplinary student teams engage in semester-long design projects. In addition to projects that are funded by local industry, faculty research grants or departmental budgets, a Venture Capital Fund has been created, which is specifically ear-marked for the development of original student inventions. Funding of up to $2,500 per student team per semester is competitively awarded based on student-generated proposals to the Venture Capital Fund, which has been created through a series of grants from the National Collegiate Inventors and Innovators Alliance (NCIIA). To qualify for funding, a multidisciplinary student team must propose, plan and implement an original, semester-long product development enterprise. To date, 11 projects have been funded through the Venture Capital Fund. This paper describes the results of several student entrepreneurial projects and compares the results of student surveys to assess the effectiveness of entrepreneurial projects in satisfying the technical objectives of the Engineering Clinic. The results suggest that students engaged in entrepreneurial projects devote more hours per week on their projects, have more "ownership" in their projects and have a better understanding of the technical aspects and societal impact of their projects than their counterparts who are engaged in the more traditional engineering design projects. [ABSTRACT FROM AUTHOR]

A recent development in antithrombotic research allows the inhibition of platelet aggregation via protection of the glycoprotein IIb/IIIa receptor on the platelet membrane. We hypothesized that a GP IIb/IIIa receptor inhibitor would inhibit thromboxane-induced platelet aggregation during circulation in our in vitro ventricular assist device (VAD) circuit and preserve long-term platelet function. Twenty-one in vitro nonpulsatile centrifugal VAD circuits were simulated for 4 days using 450 ml of fresh human whole blood with or without glycoprotein IIb/IIIa receptor inhibitor (tirofiban). Platelet aggregation and degranulation were measured in whole blood induced by ristocetin, collagen, ADP, and thromboxane A2 (TXA2). The tirofiban-treated group preserved the platelet count and tended to exert these beneficial effects by inhibiting pathologic platelet aggregation induced by TXA2, collagen, and ADP as well as degranulation. Tirofiban may be useful in preserving platelet number and function during clinical VAD use. [ABSTRACT FROM AUTHOR]