ABSTRACT
Dielectrophoresis is a potential candidate for aligning nanorods on electrodes, in which the interplay between electric fields and microfluidics is critically associated with its yield. Despite much of previous work on dielectrophoresis, the impact of frequency modulation on dielectrophoresis-driven nanorod self-assembly is insufficiently understood. In this work, we systematically explore the frequency dependence of the self-alignment of silicon nanorod using a microfluidic channel. We vary the frequency from 1kHz to 1000 kHz and analyze the resulting alignments in conjunction with numerical analysis. Our experiment reveals an optimal alignment yield at approximately 100 kHz, followed by a decrease in alignment efficiency. The nanorod self-alignments are influenced by multiple consequences, including the trapping effect, induced electrical double layer, electrohydrodynamic flow, and particle detachment. This study provides insights into the impact of frequency modulation of electric fields on the alignment of silicon nanorods using dielectrophoresis, broadening its use in various future nanotechnology applications.
ABSTRACT
OBJECTIVE: To investigate the relationship between the -629C/A polymorphism in the promoter region of the CETP gene, serum Levels, lipid metabolism, and coronary heart disease (CHD) among Tianjin Han Chinese population. METHODS: A hospital-based case-control study was conducted in Tianjin Chest Hospital from 2010 October to 2011 October. The subjects underwent angiography were divided into a case group (n = 429) and a control group (n = 275). The CETP gene promoter polymorphism at position -629 was determined by restricted fragment length polymorphism using the polymerase chain reaction (PCR-RFLP) method.The serum CETP levels was determined by enzyme-linked immunosorbent assay (ELISA) method. RESULTS: (1)The lower frequency of -629A allele in Tianjin Han Chinese population was 0.408, significantly lower than that in other domestic and foreign populations (0.479-0.701, P < 0.05). (2) Variant AA genotype showed reduced CETP levels(P > 0.05) and higher HDL-C levels (P < 0.05), compared to wild CC genotype. (3) Although there was a negative trend correlation between serum CETP and HDL-C levels, it did not reach statistical significance(P > 0.05). (4)There were significant differences in the frequencies of CETP gene -629 genotype and allele between the two groups (P < 0.001),carries with CA/AA genotype and A allele showed higher risk of CHD, OR (95%CI) values were 4.627 (3.163-6.769), 8.779 (4.799-16.059) and 3.173 (2.453-4.104) respectively. There was no relationship between CETP-629C/A polymorphism and coronary artery stenosis degree(χ(2) = 3.588, P = 0.166). CONCLUSION: The frequencies of CETP gene -629 genotype and allele in the Tianjin Han Chinese population was significantly different from that in Other domestic and foreign populations. Variant AA genotype, which showed reduced CETP levels and higher HDL-C levels, is paradoxically associated with increased risk of CHD. Thus, CETP gene variation may affect coronary risk apart from the level of HDL-C.
Subject(s)
Cholesterol Ester Transfer Proteins/genetics , Cholesterol, HDL/blood , Coronary Disease/genetics , Polymorphism, Single Nucleotide , Aged , Case-Control Studies , Cholesterol Ester Transfer Proteins/blood , Coronary Disease/blood , Female , Genotype , Humans , Male , Middle Aged , Promoter Regions, GeneticABSTRACT
<p><b>OBJECTIVE</b>To investigate the relationship between the -629C/A polymorphism in the promoter region of the CETP gene, serum Levels, lipid metabolism, and coronary heart disease (CHD) among Tianjin Han Chinese population.</p><p><b>METHODS</b>A hospital-based case-control study was conducted in Tianjin Chest Hospital from 2010 October to 2011 October. The subjects underwent angiography were divided into a case group (n = 429) and a control group (n = 275). The CETP gene promoter polymorphism at position -629 was determined by restricted fragment length polymorphism using the polymerase chain reaction (PCR-RFLP) method.The serum CETP levels was determined by enzyme-linked immunosorbent assay (ELISA) method.</p><p><b>RESULTS</b>(1)The lower frequency of -629A allele in Tianjin Han Chinese population was 0.408, significantly lower than that in other domestic and foreign populations (0.479-0.701, P < 0.05). (2) Variant AA genotype showed reduced CETP levels(P > 0.05) and higher HDL-C levels (P < 0.05), compared to wild CC genotype. (3) Although there was a negative trend correlation between serum CETP and HDL-C levels, it did not reach statistical significance(P > 0.05). (4)There were significant differences in the frequencies of CETP gene -629 genotype and allele between the two groups (P < 0.001),carries with CA/AA genotype and A allele showed higher risk of CHD, OR (95%CI) values were 4.627 (3.163-6.769), 8.779 (4.799-16.059) and 3.173 (2.453-4.104) respectively. There was no relationship between CETP-629C/A polymorphism and coronary artery stenosis degree(χ(2) = 3.588, P = 0.166).</p><p><b>CONCLUSION</b>The frequencies of CETP gene -629 genotype and allele in the Tianjin Han Chinese population was significantly different from that in Other domestic and foreign populations. Variant AA genotype, which showed reduced CETP levels and higher HDL-C levels, is paradoxically associated with increased risk of CHD. Thus, CETP gene variation may affect coronary risk apart from the level of HDL-C.</p>