ABSTRACT
Objective Interface pressure, the sine qua non for compression therapy, is rarely measured in clinical practice and scientific research. The goal of this study aimed to compare and examine the accuracy between a commercially available piezoresistive sensor and PicoPress® (Microlab, Padua, Italy) using the cylinder cuff model to measure in-vitro interface pressure. Method Ten piezoresistive sensors were calibrated using the National Institute of Standard and Technology certified manometer, and compared to PicoPress® using cylinder cuff model from 20 to 120 mmHg. Two statistical analyses were performed: (a) two-sample t-test to compare the front to back surface of the piezoresistive sensors using mean pressure value and (b) one-sample paired t-test to compare the front and back surface of the piezoresistive sensors to PicoPress® and true pressure using mean pressure value. Result There was no difference in interface pressure measurement between the front and back surface of the piezoresistive sensors (P > 0.05). Using mean pressure value, there was no significant difference between the front surface, back surface of the piezoresistive sensors, and PicoPress® (P > 0.05). Standard deviation was larger for the piezoresistive sensors than PicoPress® at any given pressure and this difference was more pronounced in the higher pressure range. Conclusion Piezoresistive sensor may represent a viable alternative to PicoPress® in interface pressure measurement.
Subject(s)
Pressure , Stockings, Compression , Vascular Diseases/diagnosis , Vascular Diseases/therapy , Calibration , Chronic Disease , Equipment Design , Humans , Lymphedema/therapy , Models, Statistical , Polyethylene Terephthalates/chemistryABSTRACT
Natural genetic promoters are regulated by multiple cis and trans regulatory factors. For quantitative studies of these promoters, the concentration of only a single factor is typically varied to obtain the dose response or transfer function of the promoters with respect to the factor. Such design of experiments has limited our ability to understand quantitative, combinatorial interactions between multiple regulatory factors at promoters. This limitation is primarily due to the intractable number of experimental combinations that arise from multifactorial design of experiments. To overcome this major limitation, we integrate impact printing and cell-free systems to enable multi-dimensional studies of genetic promoters. We first present a gradient printing system which comprises parallel piezoelectric cantilever beams as a scalable actuator array to generate droplets with tunable volumes in the range of 100 pL-10 nL, which facilitates highly accurate direct dilutions in the range of 1-10 000-fold in a 1 µL drop. Next, we apply this technology to study interactions between three regulatory factors at a synthetic genetic promoter. Finally, a mathematical model of gene regulatory modules is established using the multi-parametric and multi-dimensional data. Our work creates a new frontier in the use of cell-free systems and droplet printing for multi-dimensional studies of synthetic genetic constructs.
Subject(s)
Bioprinting/instrumentation , High-Throughput Screening Assays/instrumentation , Microfluidic Analytical Techniques/instrumentation , Promoter Regions, Genetic/genetics , Synthetic Biology/methods , Bioprinting/methods , Cell-Free System , DNA/chemistry , DNA/genetics , Gene Expression Regulation , High-Throughput Screening Assays/methods , Luminescent Proteins/chemistry , Microfluidic Analytical Techniques/methods , Synthetic Biology/instrumentationABSTRACT
Three-dimensional (3D) structure with through silicon via (TSV) technology is emerging as a key issue in microelectronic packaging industry, and electrical reliability has become one of the main technical subjects for the TSV designs. However, criteria used for TSV reliability tests have not been consistent in the literature, so that the criterion itself becomes a technical argument. To this end, this paper first performed several different reliability tests on the testing packaging with TSV chains, then statistically analyzed the experimental data with different failure criteria on resistance increasing, and finally constructed the Weibull failure curves with parameter extractions. After comparing the results, it is suggested that using different criteria may lead to the same failure mode on Weibull analyses, and 65% of failed devices are recommended as a suitable termination for reliability tests.
