Composite optical measurement systems are widely used in the field of precision measurement due to their combination of inspection with high accuracy, speed, wide range, real-time, and other advantages. Whereas errors are prevalent in measurements, in order to improve detection accuracy, the systems must be compensated for geometric errors in three-dimensional space. Aiming at the complex situation of multi-probes and multi-zooms in the composite optical measurement system, the current error modelling methods are difficult to be directly applied, so this paper establishes a unified three-dimensional volumetric error model based on the theory of multi-body system and combined with the principle of geometric optics, performs the error verification through the direct measurement method, and finally realises the compensation of geometric error in the continuous space of the whole measurement range.
View Article and Find Full Text PDFThe human hand interacts with the environment via physical contact, and tactile information is closely associated with finger movement patterns. Studying the relationship between motor primitives of the finger and the corresponding tactile feedback provides valuable insight into the nature of touch and informs the simulation of humanoid tactile. This research decomposed finger contact into three fundamental motor primitives: contact-on, stick-to-slip, and full slip, then examined the tactile features associated with each motor primitive, including the center of mass (COM) and the centroid of the contact pressure distribution matrix and the total contact area.
View Article and Find Full Text PDFWe proposed a calibration method for high-precision zoom lenses of optical measurement machines based on Fully Connected Neural Network (FNN), using a 5-layer neural network instead of a camera calibration model, to achieve continuous calibration of zoom lenses at any zoom setting by calibrating typical zooms. From the experimental verification, the average calibration error of this method is 9.83×10mm and the average measurement error at any zoom setting is 0.
View Article and Find Full Text PDFThe manipulation of microscale bioentities is desired in many biological and biomedical applications. However, the potential unobservable damage to bioparticles due to rigid contact has always been a source of concern. Herein, a soft-contact acoustic microgripper to handle microparticles to improve the interaction safety is introduced.
View Article and Find Full Text PDFBackground: Neisseria gonorrhoeae (N.g) is Gram-negative bacteria and can lead to endometritis in female. Toll-like receptors regulate immune response in various diseases.
View Article and Find Full Text PDFUnstable liquid flow in syringe pump-driven systems due to the low-speed vibration of the step motor is commonly observed as an unfavorable phenomenon, especially when the flow rate is relatively small. Upon the design of a convenient and cost-efficient microfluidic standing air bubble system, this paper studies the physical principles behind the flow stabilization phenomenon of the bubble-based hydraulic capacitors. A bubble-based hydraulic capacitor consists of three parts: tunable microfluidic standing air bubbles in specially designed crevices on the fluidic channel wall, a proximal pneumatic channel, and porous barriers between them.
View Article and Find Full Text PDFMicrobubbles are often used in chemistry, biophysics, and medicine. Properly controlled microbubbles have been proved beneficial for various applications by previous scientific endeavors. However, there is still a plenty of room for further development of efficient microbubble handling methods.
View Article and Find Full Text PDFTo explore and utilize the advantages of droplet-based microfluidics, hydrodynamics, and mixing process within droplets traveling though the T junction channel and convergent-divergent sinusoidal microchannels are studied by numerical simulations and experiments, respectively. In the T junction channel, the mixing efficiency is significantly influenced by the twirling effect, which controls the initial distributions of the mixture during the droplet formation stage. Therefore, the internal recirculating flow can create a convection mechanism, thus improving mixing.
View Article and Find Full Text PDFThe efficacy of DNA vaccines may be improved by small interfering (si)RNA adjuvants targeting pro-apoptotic genes. The aim of the present study was to investigate the capacity of siRNAs targeting B-cell lymphoma 2 homologous antagonist killer (BAK) and B-cell lymphoma 2-associated X protein (BAX) to improve the efficacy of a cytomegalovirus (CMV) vaccine. BALB/c mice were divided into four groups (n=18 in each): unimmunized and immunized with pcDNA 3.
View Article and Find Full Text PDFBiomicrofluidics
September 2015
To sequentially handle fluids is of great significance in quantitative biology, analytical chemistry, and bioassays. However, the technological options are limited when building such microfluidic sequential processing systems, and one of the encountered challenges is the need for reliable, efficient, and mass-production available microfluidic pumping methods. Herein, we present a bubble-free and pumping-control unified liquid handling method that is compatible with large-scale manufacture, termed multilayer microfluidic sample isolated pumping (mμSIP).
View Article and Find Full Text PDFAim: To explore the correlation between Twist-related protein (Twist)1, fibroblast growth factor receptor (FGFR)2 and gastric adenocarcinoma differentiation and progression.
Methods: We evaluated Twist1 and FGFR2 in 52 gastric adenocarcinoma samples by immunohistochemistry and quantitative real time polymerase chain reaction, and analyzed the correlation between Twist1, FGFR2 and cancer differentiation. We also detected Twist1 and FGFR2 expression in gastric adenocarcinoma cell lines, and evaluated Twist1 influence on FGFR2 expression.
Zhongguo Zhong Xi Yi Jie He Za Zhi
August 2005
Objective: To study the inhibitory effect of Jinye Baidu Preparation (JBP), a Chinese medicinal preparation, on human cytomegalovirus protein kinase pu197 and to explore its molecular mechanism in treating human cytomegalovirus (HCMV) infection.
Methods: Expression of the HCMV pu197mRNA in infected cells was measured by semi-quantitative RT-PCR before and after intervention of JBP or Ganciclovir (GCV), and effect of the two medicines on the proliferation activity of the infected cells was observed by MTT.
Results: Both JBP and GCV showed obvious inhibitory action on HCMV pu197mRNA.
In this study, we investigated the anti-vasculature effects and the antitumor effects of combining attenuated Salmonella typhimurium vaccine strain encoding murine vascular endothelial growth factor (VEGF) receptor-2 (flk1) with plasmid DNA vector encoding the murine interleukin-12 (mIL-12) gene. In combination, flk1 based DNA vaccine and mIL-12 slowed down tumor growth more effectively than either one alone. Splenocytes from the combined group were showed a strong CTL response against both the flk1 and tumor cells.
View Article and Find Full Text PDFCancer Biother Radiopharm
October 2004
Aim: The aim of this study was to investigate the antivasculature effects and the antitumor effects of combining attenuated Salmonella typhimurium vaccine strain encoding murine vascular endothelial growth factor (VEGF) receptor-2 (flk1) with plasmid DNA vector encoding the murine IL-12 (mIL-12) gene.
Methods: Mouse models of Gl261 glioblastoma were treated with combining orally given attenuated Salmonella typhimurium vaccine strain encoding flk1 with direct intratumoral injection of a nonviral plasmid DNA vector encoding the murine IL-12 (mIL-12) gene. The volumes of tumors were observed.