Pressure control model for transport of liquid mercury in carbon nanotubes

Background: Uncontrolled hypertension increases patients’ risk for cardiovascular and kidney disease. This study compared strategies to improve systolic blood pressure (SBP) among 1000 simulated patients with uncontrolled hypertension (SBP >=140 mmHg) from the National Health and Nutrition Examination Survey (NHANES). Methods: The Blood Pressure Control Model (BPCM) is a microsimulation, health state transition model that predicts the weekly SBP of patients receiving usual care. In the BPCM, patient SBPs are estimated using office visit frequency, measured SBP accuracy and variability, probability of treatment intensification with uncontrolled SBP, effect of antihypertensive medications, and adherence. BPCM inputs are derived from national survey data, meta-analyses, and other published literature. The effects of usual care on SBP were compared to 10% and 50% increases in global strategies for SBP control (i.e., visit frequency, treatment intensification, and/or adherence) over 10 years. SBP outcomes were validated against published literature values of 44-46% prior to implementation (i.e., usual care) and 74-80% 8-10 years after implementation of aggressive hypertension management programs in large health systems. Results: In the simulated NHANES population, the mean (SD) age was 61.1 (14.6), 52% were male, and mean baseline SBP was 153.2 (13.6) mmHg. Under usual care, the BPCM estimated a mean SBP of 140.1 (16.4) mmHg and 49% of patients achieving SBP <140 mmHg after 10 years. Compared to usual care, 50% improvements in global strategies resulted in more rapid reductions in SBP and earlier achievement of SBP control. Simultaneously improving all global strategies by 50% resulted in an estimated mean SBP of 132.4 (15.5) mmHg with 71% achieving control after 10 years. Conclusions: Usual care and intervention BPCM predictions are consistent with hypertension control rates observed in contemporary national surveys and the observed results of recent systematic hypertension control improvement programs. These results show the BPCM may be used by health system planners to project the impact of implementing hypertension control strategies.

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A Pressure Control Method for Emulsion Pump Station Based on Elman Neural Network

Computational Intelligence and Neuroscience ◽

10.1155/2015/684096 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Chao Tan ◽

Nan Qi ◽

Xin Zhou ◽

Xinhua Liu ◽

Xingang Yao ◽

...

Keyword(s):

Neural Network ◽

Control Method ◽

Pressure Control ◽

Control Model ◽

System Framework ◽

Elman Neural Network ◽

Pump Station ◽

Comparison Results ◽

Safety Production ◽

Key Techniques

In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was feasible and efficient and outperformed others.

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Structural phenomena in the growth of carbon nanotubes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149581 ◽

1993 ◽

Vol 51 ◽

pp. 750-751

Author(s):

Jun Jiao

Keyword(s):

Carbon Nanotubes ◽

Growth Mechanism ◽

Carbonaceous Material ◽

Cluster Growth ◽

Structural Elements ◽

Rich Variety ◽

Different Shapes ◽

Point To Point

HREM studies of the carbonaceous material deposited on the cathode of a Huffman-Krätschmer arc reactor have shown a rich variety of multiple-walled nano-clusters of different shapes and forms. The preparation of the samples, as well as the variety of cluster shapes, including triangular, rhombohedral and pentagonal projections, are described elsewhere.The close registry imposed on the nanotubes, focuses attention on the cluster growth mechanism. The strict parallelism in the graphitic separation of the tube walls is maintained through changes of form and size, often leading to 180° turns, and accommodating neighboring clusters and defects. Iijima et. al. have proposed a growth scheme in terms of pentagonal and heptagonal defects and their combinations in a hexagonal graphitic matrix, the first bending the surface inward, and the second outward. We report here HREM observations that support Iijima’s suggestions, and add some new features that refine the interpretation of the growth mechanism. The structural elements of our observations are briefly summarized in the following four micrographs, taken in a Hitachi H-8100 TEM operating at an accelerating voltage of 200 kV and with a point-to-point resolution of 0.20 nm.

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