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Reporting and Discussing Effect Size: Still the Road Less Traveled?
This study shows the extent to which effect size is reported and discussed in four major journals. A series of judgments about different aspects of effect size were conducted for 417 articles from four journals. Results suggest that while the reporting of simple effect size indices is more prevalent, substantive discussions of the meaning of effect size is lacking. Accessed 17,478 times on https://pareonline.net from October 18, 2011 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right
PENETRATION OF HIGH VELOCITY HORIZONTAL GAS JETS INTO A FLUIDIZED BED AT HIGH TEMPERATURE
High velocity horizontal gas jets are applied to various industrial processes. In this work, a new thermal technique has been developed to measure the penetration length of horizontal gas jets. Experiments were conducted in a fluidized bed with a height of 1.23m and a rectangular cross section of 0.10m × 0.50m. The fluidized bed particles, which were either petroleum coke or sand, were heated by an in-bed electrical heater to temperatures between 300°C and 500°C. Cold gases, such as helium, nitrogen, carbon dioxide, were injected into the hot fluidized bed via a horizontal nozzle operating over a range of velocities. Based on the experimental results, a new empirical correlation was developed to predict the penetration length of jets issuing from the horizontal sonic nozzle at high temperature
STUDY OF SOLIDS ENTRAINMENT INTO ATTRITION JETS IN FLUIDIZED BEDS
Supersonic nozzles are applied to various fluidized bed processes, such as the production of pharmaceutical powders, fluid catalytic cracking, and fluid coking. In applications such as jet milling, it is essential to entrain a maximum flow-rate of solids from the fluidized bed into the jet cavity. Studies of solid entrainment rate into gas jets have been mostly conducted with subsonic jets and none with convergent-divergent nozzles. The purpose of this research is to study solids entrainment into jets issuing from supersonic convergent-divergent nozzles, and particularly the effects of nozzle size, nozzle mass flow-rate, injection gas properties and fluidization velocity. A novel accurate technique is developed to measure solids entrainment into jets
Analysis of the mechanism of transferrin-iron acquisition by Neisseria gonorrhoeae
Neisseria gonorrhoeae is an obligate human pathogen that requires iron for its survival within the host. N. gonorrhoeae expresses high-affinity iron acquisition systems to acquire iron from host iron binding proteins. The gonococcal transferrin-iron uptake system is composed of two transferrin binding proteins, TbpA and TbpB. TbpA is a TonB-dependent, outer membrane transporter, while TbpB is a surface-exposed lipoprotein. Unlike TbpA, TbpB is not required for transferrin utilization, but makes the process more efficient. The precise mechanism by which TbpA and TbpB function to mediate transferrin-iron uptake has not been fully characterized. However, the mechanism of iron acquisition from transferrin is distinct from characterized TonB-dependent ferric-siderophore uptake systems. The transferrin-iron uptake system is unique in two ways: the involvement of the TbpB lipoprotein component and the process of iron acquisition and internalization. Unlike siderophore transporters, the transferrin-iron uptake system requires the removal of iron from transferrin for its subsequent internalization. Based on analogy with characterized TonB-dependent transporters, TbpA is proposed to consist of two distinct domains: a b-barrel and plug domain. Previous studies suggest that the plug domain has a specific role in iron internalization and this study addresses the role of the plug domain in transferrin-iron acquisition. It is thought that the TbpA plug domain facilitates iron removal from transferrin and subsequent iron binding and transport. To analyze this, iron binding by the TbpA plug domain was performed and site-directed substitution mutagenesis of putative iron-coordinating residues was carried out. From these analyses, it can be concluded that the plug domain binds iron and likely plays an active role in the process of iron internalization. Mutagenesis revealed specific residues of the plug domain critical for transferrin-iron uptake, but defects imparted by these mutations were compensated for by TbpB. Thus, this study also attempts to characterize the compensatory function provided by TbpB. Through mutagenesis, critical domains involved in the efficiency of transferrin-iron acquisition were identified. One additional study describes and characterizes a novel mechanism of TonB-independent transferrin-iron acquisition. Overall, these studies further elucidate mechanisms utilized by Neisseria gonorrhoeae in the process of iron acquisition from human transferrin
Relationship between employment and mental health outcomes following Cardiac Rehabilitation : an observational analysis from the National Audit of Cardiac Rehabilitation
BACKGROUND: Employment status has been shown to impact mental health state and intervention outcomes, yet still to be studied in a Cardiac Rehabilitation (CR) population. This observational study investigated the relationship between employment status and mental health outcomes following Cardiac Rehabilitation (CR). METHODS: All patients with an eligible cardiovascular incident entered into the National Audit of Cardiac Rehabilitation (NACR) 1 January 2013-31st December 2015. Logistic regression comparing the association between employment status and normal mental health categories. RESULTS: A total of 24,242 CR patients with completed post CR assessments were included and had representative age and gender distribution (mean 65years, 73.2% male). At baseline the unemployed status had a lower proportion of patients in normal healthy categories than other groups (T-test and chi-squared p=<0.05). The regression analyses revealed no significant association between retired and employed groups and outcome. There was significant association between unemployed patients and all mental health outcomes except anxiety; all p values<0.05 and odds ratios between 0.525 and 0.772 showing less likelihood of achieving the normal healthy category. CONCLUSIONS: This is the first UK study, using routinely collected data, to investigate in coronary heart disease patients the impact of employment status on outcomes. The findings were that when weighted for baseline differences, unemployed patients mostly had poorer outcomes. Teams involved in CR delivery should take particular care when interpreting mental health baseline measures when setting CR goals, especially in relation to unemployed patients, and efforts should be made in providing more patient tailored interventions
Study of High Velocity Attrition Nozzles in a Fluidized Bed
The objective of this study was to test different high velocity attrition nozzles and operating conditions in order to determine the effects of various parameters on the grinding efficiency. Nozzle geometry, as well as gas properties such as speed of sound and density had a significant impact on the grinding efficiency. In addition, a model was developed in order to understand the particle breakage mechanisms during particle attrition. The model showed that the primary attrition mechanism was the splitting of particles rather than their erosion
Signal transduction and activator of transcription-3 (STAT3) in patients with colorectal cancer: associations with the phenotypic features of the tumour and host
Purpose: In patients with colorectal cancer (CRC), a high-density local inflammatory infiltrate response is associated with improved survival, whereas elevated systemic inflammatory responses are associated with poor survival. One potential unifying mechanism is the IL-6/JAK/STAT3 pathway. The present study examines the relationship between tumour total STAT3 and phosphorylated STAT3Tyr705 (pSTAT3) expression, host inflammatory responses and survival in patients undergoing resection of stage I-III CRC. Experimental Design: Immunohistochemical assessment of STAT3/pSTAT3 expression was performed using a tissue microarray and tumour cell expression divided into tertiles using the weighted histoscore. The relationship between STAT3/pSTAT3 expression and local inflammatory (CD3+, CD8+, CD45R0+, FOXP3+ T-cell density and Klintrup-Mäkinen grade) and systemic inflammatory responses and cancer-specific survival were examined. Results: 196 patients were included in the analysis. Cytoplasmic and nuclear STAT3 expression strongly correlated (r=0.363, P<0.001); nuclear STAT3 and pSTAT3 expression weakly correlated (r=0.130, P=0.068). Cytoplasmic STAT3 was inversely associated with the density of CD3+ (P=0.012), CD8+ (P=0.003) and FOXP3+ T-lymphocytes (P=0.002) within the cancer cell nests and was associated with an elevated systemic inflammatory response as measured by modified Glasgow Prognostic Score (mGPS2: 19% vs. 4%, P=0.004). The combination of nuclear STAT3/pSTAT3 stratified five-year survival from 81% to 62% (P=0.012), however was not associated with survival independent of venous invasion, tumour perforation or tumour budding. Conclusion In patients undergoing CRC resection, STAT3 expression was associated with adverse host inflammatory responses and reduced survival. Up-regulation of tumour STAT3 may be an important mechanism whereby the tumour deregulates local and systemic inflammatory responses
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