RESUMEN
In order to achieve the high-precision and high-efficiency machining of micro-channels for hard and brittle materials, the authors innovatively proposed a new technology called template-based electrophoretically assisted micro-ultrasonic machining (TBEPAMUSM). This technology transfers the micro-channel shape punch-pin to the workpiece material through micro-ultrasonic machining to form a micro-channel. At the same time, it uses the electrophoretic properties of ultra-fine abrasive particles to ensure the existence of abrasive particles in the machining area by applying a DC electric field. According to the new technology machining principle, a machine tool of TBEPAMUSM was designed and developed. The machine tool hardware adopts a C-shaped structure, including a marble platform, an ultrasonic vibration system, a micro three-dimensional motion platform, a working fluid tank, and a pressure sensor. The machine tool intelligent control system is developed based on LabVIEW, including the initialization module, fast positioning module, constant force tool setting module, constant force control machining module, and real-time coordinate display module. Micro-channels with different structures are machined on single-crystal silicon and soda-lime glass using the designed machine tool and the developed control system. The results show that: when electrophoresis assistance is applied in machining, the edge chipping phenomenon of the micro-channel is significantly reduced, the surface roughness is reduced by about 20%, and the machining efficiency is increased by about 4%.
RESUMEN
Patients with gastric cancer (GC) have a poor prognosis, which is mainly due to the low rate of early diagnosis. The present study aimed to evaluate whether circulating microRNA-130b (miR-130b) and blood routine parameters [neutrophil count (N#), lymphocyte count (L#), monocyte count (M#), neutrophil percentage (N%), lymphocyte percentage (L%), monocyte percentage (M%), hemoglobin (Hb) level, hematocrit (Hct), red blood cell distribution width (RDW), platelet count, platelet distribution width (PDW), mean platelet volume (MPV), MPV to platelet count ratio (MPV/PC), monocyte to lymphocyte ratio (MLR), neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR)] are useful biomarkers for GC, early stage GC (EGC) and precancerous lesion (Pre) detection, and to identify more effective diagnostic models by combining circulating blood markers. Circulating levels of M#, M%, RDW-coefficient of variation (RDW-CV), MPV, PDW, MLR and NLR were significantly higher, and the levels of Hb and L% were significantly lower in patients with GC and Pre compared with those in healthy controls (NCs) (all P<0.05). The N#, N% and PLR in patients with GC were significantly higher and the Hct was significantly lower than those in the NCs (all P<0.05). The values of MPV/PC were significantly higher in the Pre cohort compared with those in the NCs. The area under the curve (AUC) of the receiver operating characteristic curve of potential biomarkers for GC was 0.634-0.887 individually, and this increased to 0.978 in the combination model of miR-130b-PDW-MLR-Hb. Additionally, the values for RDW-CV, PLR, NLR, N# and N% were positively correlated with cancer stage, while the values for MPV, L#, L%, Hb and Hct were negatively correlated with cancer stage. Furthermore, the circulating levels of miRNA-130b, and the values for NLR, RDW-CV, PDW, M%, red blood cell count, Hct, Hb and MLR differed between the EGC and NC groups. The AUC values of these biomarkers were 0.6491-0.911 individually in the diagnosis of EGC, and these increased to 0.960 in combination. In addition, the AUC values for miR-130b, RDW-CV, MPV/PC ratio, MLR, NLR, PDW, L%, M%, M# and Hb in the diagnosis of Pre were 0.638-0.811 individually. The dual-model of miR-130b-PDW manifested the largest AUC of 0.896 in the diagnosis of Pre, and the sensitivity and accuracy were increased when miR-130b and PDW were combined. All these results suggested that circulating miR-130b and blood routine parameters might be potential biomarkers, and combinations of measurements of these biomarkers may improve the GC, EGC and Pre diagnostic accuracy.