A MEMS-Based Flow Rate and Flow Direction Sensing Platform with Integrated Temperature Compensation Scheme

This study develops a MEMS-based low-cost sensing platform for sensing gas flow rate and flow direction comprising four silicon nitride cantilever beams arranged in a cross-form configuration, a circular hot-wire flow meter suspended on a silicon nitride membrane, and an integrated resistive temperature detector (RTD). In the proposed device, the flow rate is inversely derived from the change in the resistance signal of the flow meter when exposed to the sensed air stream. To compensate for the effects of the ambient temperature on the accuracy of the flow rate measurements, the output signal from the flow meter is compensated using the resistance signal generated by the RTD. As air travels over the surface of the cross-form cantilever structure, the upstream cantilevers are deflected in the downward direction, while the downstream cantilevers are deflected in the upward direction. The deflection of the cantilever beams causes a corresponding change in the resistive signals of the piezoresistors patterned on their upper surfaces. The amount by which each beam deflects depends on both the flow rate and the orientation of the beam relative to the direction of the gas flow. Thus, following an appropriate compensation by the temperature-corrected flow rate, the gas flow direction can be determined through a suitable manipulation of the output signals of the four piezoresistors. The experimental results have confirmed that the resulting variation in the output signals of the integrated sensors can be used to determine not only the ambient temperature and the velocity of the air flow, but also its direction relative to the sensor with an accuracy of ± 7.5° error

Electrogenic capabilities of gram negative and gram positive bacteria in microbial fuel cell combined with biological wastewater treatment

The voltage and the power production of two gram negative and two gram positive bacteria in four identical continuous flow microbial fuel cells combined with biological wastewater treatment units were evaluated and compared in the present study. Each microbial fuel cell and biological treatment unit was operated at four different flow rates and four different external load resistances. The results show that overall removal efficiency of chemical oxygen demand for all four systems can reach more than 85.5%. Each pure culture has different power generation performance that can be affected by some factors, such as wastewater characteristics, influent flow rate and hydraulic retention time of reactor. Good linear relationships between the flow rate and the potential and between the flow rate and the power density on four pure cultures at different external load resistances were found. Comamonas testosteroni has better power generation performance than Arthrobacter polychromogenes , especially at higher flow rate. Although Pseudomonas putida also showed higher power generation than Corynebacterium glutamicum , the difference was not statistically significant. It seems that gram negative bacteria could display higher power generation than gram positive bacteria at higher flow rate. However, more evidence is required to provide stronger proof for the difference of power generation between gram negative and gram positive bacteria

A study on chitosan modification of polyester fabrics by atmospheric pressure plasma and its antibacterial effects

Chitosan is a natural nontoxic biopolymer used widely in various fields due to the antimicrobial activities. In this study, the properties of polyester fabrics grafted with chitosan oligomers/polymers after being activated by atmospheric pressure plasmas were evaluated. The antibacterial effect was most evident when the surface of fabrics was activated by atmospheric pressure plasma for 60 to 120 seconds and grafted with chitosan oligomers. The modified fabrics also exhibited good biocompatibility. This process can be applied to a large area and used to produce antibacterial polymer fibers

Gender Differences In Stress And Coping Among Elderly Patients On Hemodialysis

The study investigated whether gender differences in the stressor, coping strategies, and how they associate stress and copings among 875 elderly patients undergoing hemodialysis in Taiwan. Chi-square tests, MANOVA and Structural Equation Modeling were used to attain the research purposes. The results found that the women had reported higher stress in response to physical and vessel problems and higher scores in using emotion-oriented and support-seeking coping strategies, while the men reported higher stress in reproductive system functioning and higher score in using avoidance as a coping strategy. Furthermore, the results from SEM demonstrated that after controlling for patient characteristics, no statistical difference was found between the two groups with regard to their linking of stress and coping strategies. © 2008 Springer Science+Business Media, LLC

Nylon textiles grafted with chitosan by open air plasma and their antimicrobial effect

Chitosan is a natural non-toxic biopolymer and is widely used in various fields because of the antimicrobial activities. In this study, the properties of nylon textiles grafted with chitosan oligomer or chitosan polymer after being activated by open air plasma were evaluated. Results showed that nylon textiles grafted with chitosan polymer had better antibacterial performances than those grafted with chitosan oligomer. Air plasma activation at a higher speed (26 m/min) for a few times facilitated the grafting of chitosan and critically determined the antibacterial activities. Further treatment with air plasma after grafting improved the antibacterial effect. Overall, chitosan-grafted nylon textiles showed good antibacterial potential as well as biocompatibility

The Influence Of Facility Ownership Structure On Individual Responding To Stress: A Multilevel Model

Few studies have investigated the effect of health-care facility ownership on the relationship between patient stressors and coping strategies. The purpose of this study was to investigate whether haemodialysis (HD) patient stressors and coping strategies differ by type of health-care facility ownership, and whether such ownership has a cross-level moderating effect between stressors and coping strategies. We used the Haemodialysis Stressor Scale and the Jalowiec Coping Scale; primary data were collected by interviewing 2642 HD patients 15 years or older on dialysis for at least three months from 27 HD centres. One-way analysis of variance and hierarchical linear modelling were used to attain the research purposes. HD patients from religious-based hospitals had higher stress related to their physical symptoms, dependency on medical staff, role ambiguity and blood vessel problems than those differently owned facilities. Patients in veterans and army (VA) hospitals had higher stress related to food and fluid restriction and dependency on medical staff than private centres. Patients in religious-based hospitals had significantly higher coping scores, followed by VA and private HD centres. Religion-based ownership might serve as a cross-level moderator for patients perceiving role ambiguity stress and using problem-oriented, support seeking and isolated thought-coping strategies

Fabrication of GaN-based nanorod light emitting diodes using self-assemble nickel nano-mask and inductively coupled plasma reactive ion etching

We report a novel method to fabricate GaN-based nanorod light emitting diodes (LEDs) with controllable dimension and density using self-assemble nickel (Ni) and Ni/Si3N4 nano-masks and inductively coupled plasma reactive ion etching (ICP-RIE). Under the fixed Cl-2/Ar flow rate of 50/20 sccm. ICP/Bias power of 400/100 W and chamber pressure of 0.67 Pa, the GaN-based nanorod LEDs were fabricated with density of 2.2 x 10(9) to 3 x 10(10) cm(-2) and dimension of 150-60 nm by self assemble Ni nano-masks with various size. The size of Ni/Si3N4 nano-mask was control by the thickness Ni film ranging 150-50 Angstrom and rapid thermal annealing condition. The technique offers a controllable method of fabrication of GaN-based nanorod LEDs and should be applicable for fabrication of the others III-V nanoscale photonic and electronic devices. (C) 2004 Elsevier B.V. All rights reserved

Fabrication of InGaN/GaN nanorod light-emitting diodes with self-assembled Ni metal islands

We report the fabrication of InGaN/GaN nanorod light-emitting diodes (LEDs) using inductively coupled plasma reactive-ion etching (ICP-RIE) and a photo-enhanced chemical (PEC) wet oxidation process via self-assembled Ni nanomasks. An enhancement by a factor of six times in photoluminescence (PL) intensities of nanorods made with the PEC process was achieved in comparison to that of the as-grown structure. The peak wavelength observed from PL measurement showed a blue shift of 3.8 nm for the nanorods made without the PEC oxidation process and 8.6 nm for the nanorods made with the PEC oxidation process from that of the as-grown LED sample. In addition, we have demonstrated electrically pumped nanorod LEDs with the electroluminescence spectrum showing more efficiency and a 10.5 nm blue-shifted peak with respect to the as-grown LED sample

IL-10 and TNF-alpha promoter polymorphisms in susceptibility to systemic lupus erythematosus in Taiwan

Objective The genetic control of Interleukin-10 (IL-10) and Tumour necrosis factor-alpha (TNF-alpha) production and the possible interaction between the two cytokines in influencing SLE susceptibility as well as clinical features has not been completely evaluated in the Taiwanese population. Methods We investigated the association of IL-10 and TNF-alpha promoter polymorphisms (-1082, -819 and -592 for IL-10 gene; -308 for TNF-alpha gene) with SLE in a total of 172 Taiwanese patients and 215 controls. Results Our results indicate that IL-10 A/T/A-A/T/A genotype was associated with Taiwanese SLE, whereas no significance was observed between TNF-alpha genotype and SLE. Furthermore, the TNF-alpha G allele frequency of the polymorphism at -308 was significantly decreased in patients with oral ulcers. The combined frequencies of IL-10 A/T/A haplotype and TNF-alpha G-G genotype were significantly increased in SLE patients. In addition, the combined frequencies of IL-10 A/T/A haplotype and TNF-alpha G-G genotype were significantly decreased in patients with oral ulcers. Conclusion These results suggest a significant correlation of the combined IL-10 and TNF-alpha genetic polymorphisms contribute to SLE susceptibility and clinical features in the Taiwanese population

Danthron Inhibits Murine WEHI-3 Cells In Vivo, and Enhances Macrophage Phagocytosis and Natural Killer Cell Cytotoxic Activity in Leukemic Mice

Danthron has been shown to induce apoptotic cell death, and inhibit migration and invasion of human gastric or brain cancer cells in vitro. However, there is no report addressing whether danthron affects murine leukemia cells or immune responses in vivo. Herein, this study focused on the in-vivo effects of danthron on WEHI-3 leukemia in mice and immune responses in vivo. The results indicated that danthron reduced spleen weight and increased the percentage of cells with CD3 and CD19 markers, indicating that differentiation of the precursors of T- and B-cells was promoted in the leukemic mice. The results also showed that danthron promoted die activity of phagocytosis by macrophages isolated from the peritoneal cavity but had no effect on peripheral blood mononuclear cells. Danthron also promoted natural killer cell cytocytic activity at an effector and target cell ratio of 100:1 in comparison with leukemic animals in vivo. Taken together, these results demonstrated that application of danthron might affect WEHI-3 leukemia in mice and modulate immune responses in vivo