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Here, we describe a new photoelectrochemical imaging method termed light-addressable square wave voltammetry (LASWV). It measures local SWV currents at an unstructured electrolyte/insulator/semiconductor (EIS) field-effect substrate by illuminating and addressing the substrate with an intensity-constant laser. Due to the continuous generation of charge carriers in the light-irradiated semiconductor, the drift and diffusion of photoinjected carriers within the semiconductor bulk would slow down the equilibrium processes of charge and discharge in one potential pulse cycle. Therefore, even though SWV is sampled at the end of the direct and reverse pulses to reject capacitive currents, in our approach, photoinduced capacitive current can still be detected as an effective sensory signal. The obtained current-potential (I-V) curve shows a typical shape corresponding to the accumulation, depletion, and inversion regions of field-effect devices. We demonstrated that LASWV can be used as a field-effect chemical sensor to measure the solution pH and monitor enzymatic reactions. More importantly, since the charge carriers are only generated in the illuminated area, the laser spot in the device can be used as a virtual probe to record local electrochemical properties such as impedance with microresolution.

Objectives To develop a radiomics signature for predicting surgical portal vein-superior mesenteric vein (PV-SMV) in patients with pancreatic ductal adenocarcinoma (PDAC) and measure the effect of providing the predictions of radiomics signature to radiologists with different diagnostic experiences during imaging interpretation. Methods Between February 2008 and June 2020, 146 patients with PDAC in pancreatic head or uncinate process from two institutions were retrospectively included and randomly split into a training (n = 88) and a validation (n =58) cohort. Intraoperative vascular exploration findings were used to identify surgical PV-SMV invasion. Radiomics features were extracted from the portal venous phase CT images. Radiomics signature was built with a linear elastic-net regression model. Area under receiver operating characteristic curve (AUC) of the radiomics signature was calculated. A senior and a junior radiologist independently review CT scans and made the diagnosis for PV-SMV invasion both with and without radiomics score (Radscore) assistance. A 2-sided Pearson's chi-squared test was conducted to evaluate whether there was a difference in sensitivity, specificity, and accuracy between the radiomics signature and the unassisted radiologists. To assess the incremental value of providing Radscore predictions to the radiologists, we compared the performance between unassisted evaluation and Radscore-assisted evaluation by using the McNemar test. Results Numbers of patients identified as presence of surgical PV-SMV invasion were 33 (37.5%) and 19 (32.8%) in the training and validation cohort, respectively. The radiomics signature achieved an AUC of 0.848 (95% confidence interval, 0.724-0.971) in the validation cohort and had a comparable sensitivity, specificity, and accuracy as the senior radiologist in predicting PV-SMV invasion (all p-values > 0.05). Providing predictions of radiomics signature increased both radiologists' sensitivity in identifying PV-SMV invasion, while only the increase of the junior radiologist was significant (63.2 vs 89.5%, p-value = 0.025) instead of the senior radiologist (73.7 vs 89.5%, p-value = 0.08). Both radiologists' accuracy had no significant increase when provided radiomics signature assistance (both p-values > 0.05). Conclusions The radiomics signature can predict surgical PV-SMV invasion in patients with PDAC and may have incremental value to the diagnostic performance of radiologists during imaging interpretation.

A new photoelectrochemical imaging method termed scanning electrochemical photometric sensor (SEPS) is proposed in this work. It was derived from light-addressable potentiometric sensor (LAPS) and scanning photoinduced impedance microscopy (SPIM) using a front-side laser illumination at a field-effect structure. When the laser beam scans across the sensor substrate, local photocurrent changes at inversion due to the light absorption of analytes can be recorded. It will be shown that SEPS could be used for label-free living cell imaging with micro-resolution as well as real-time quantitative absorption analysis, which would broaden the applications of traditional LAPS/SPIM from potentiometric/impedance measurements to local optical analysis.

The purpose of this study was to compare comprehensive CT and MRI in the presurgical evaluation of pancreatic cancer.Thirty-eight patients with pathologically proven pancreatic cancer were included in a retrospective study. CT with negative-contrast CT cholangiopancreatography and CT angiography (CTA) (CT image set) versus MRI with MRCP and MR angiography (MRI image set) were analyzed independently by two reviewers for tumor detection, extension, metastasis, vascular invasion, and resectability. These results were compared with the surgical and pathologic findings.The rate of detection of tumors was higher with MRI than with CT but not significantly so (reviewer 1, p = 1.000; reviewer 2, p = 0.500). In the evaluation of vessel involvement, nodal status, and resectability, although CT had higher ROC AUC values than did MRI (reviewer 1, 0.913 vs 0.858, 0.613 vs 0.503, and 0.866 vs 0.774; reviewer 2, 0.879 vs 0.849, 0.640 vs 0.583, and 0.830 vs 0.815), the differences were not statistically significant (p = 0.189 vs 0.494, 0.328 vs 0.244, and 0.193 vs 0.813 for reviewers 1 and 2). In the evaluation of tumor extension and organ metastases in the 38 patients, correct diagnosis of one of two liver metastases was achieved with both image sets, one case of omental and one case of peritoneal seeding were underestimated, and one case of stomach invasion was overestimated.MRI and CT had similar performance in the presurgical evaluation of pancreatic cancer.

To investigate the effect of total flavone of haw leaves (TFHL) on the expression of nuclear factor erythroid-2 related factor (Nrf2) and other related factors in nonalcoholic steatohepatitis (NASH) rats induced by high-fat diet and then to further discuss the mechanism of TFHL’s prevention against NASH. High-fat diet was fed to 40 rats to establish the NASH model. Then model rats were intragastrically administrated with 40, 80, 160 mg/(kg•day) TFHL, respectively. The pathological changes of liver tissues in NASH rats were detected by oil red O and hematoxylin-eosin (HE) stainings. The expression of Nrf2 in rat liver was examined through immunohistochemistry. The level of 8-iso-prostaglandin F2α in serum was detected through enzyme linked immunosorbent assay (ELISA). The mRNA and protein levels of Nrf2 and other related factors in liver tissue were measured by real-time reverse transcriptionpolymerase chain reaction and western blot. Lipid deposition, hepatic steatosis, focal necrosis in lobular inflammation and ballooning degeneration were emerged in livers of NASH rats. The 8-iso-prostaglandin F2α in the serum of NASH rats increased significantly compared with the control group (P

OBJECTIVE To study and discuss the effect and mechanism of Hirsutella sinensis mycelium (HSM) on idiopathic pulmonary fibrosis in rats. METHOD Forty Wistar rats were divided into five groups: the normal control group, the model control group, the high-dose group (1.0 g x kg(-1) HSM), the low-dose group (0.5 g x kg(-1) HSM), and the positive control group (10 mg x kg(-1) hydrocortisone). In addition to rats in the normal control group, the pulmonary fibrosis model was established by injecting 5 mg x kg(-1) bleomycin into rat tracheas for consecutively 28 days, in order to observe their lung function, lung tissue hydroxyproline, cytokines and pathology. RESULT After rats were administered with HSM, 0.5 g x kg(-1) and 1.0 g x kg(-1) HSM could significantly decrease lung index and hydroxyproline content (P

In this paper, a new method of insulator fault detection by texture feature sequence is proposed. Morphology, Hough transform line detection and statistic texture feature are applied to this method. Because there are some noises during image shooting, it is necessary that the insulator image should be preprocessed and corrected. The preprocessing includes image grayness, image enhancement and morphological processing. The insulator tilt correction is based on Hough transform line detection. Then, the processed insulator image is separated into ten parts. Each part of ten parts is featured by seven texture values. The matrix is constructed by ten columns which represent ten parts and seven rows which represent seven texture features. Each row of the matrix is defined as a sequence. According to the analysis of seven feature sequence curves, three feature sequence curves are selected because they are active. A fault feature formula that is named CMV is made of the three features. Insulator fault is detected by CMV curve. The position of fault is located by the biggest vale of CMV curve. Experimental results indicate the proper morphological processing improves the precision of Hough transform line detection and the insulator fault is detected and the position of fault is located by the proposed method accurately.

In this paper, a method of tempered glass insulator recognition based on intensity in HSI modal from airborne image by helicopter on power grid is proposed. Morphology, extraction of connected components and threshold value segmentation by mean are applied to this method. The intensity of image contains the important information of insulator image, which is the base of insulator image segmentation. According to the feature of intensity in image, it is helpful that intensity image become binary image. Because there are some noises in the binary image, it is necessary that the binary image should be preprocessed to reduce noise. The erode process in morphology is used here. After above preprocessing, extraction of connected components can mark every 1 area in binary image, which includes the part of insulator and noise. Then setting threshold value range with mean in the number of every connected component is the threshold in classifying these components to insulator or not. Experimental results indicate that the method can classify insulator in image with little mistake.

Sapphire fibers with diameters of 325-850 microm were plastically bent by CO(2) laser beams with typical bending radii as small as 2.8 mm. The additional optical loss caused by a single bend was less than 0.1 dB (at 900 nm), the damage threshold of the bent fibers was higher than 150 MW/cm(2) for Nd:YAG laser pulses, and the high mechanical strength of the bending area was also proved. Several successful applications of bent sapphire fibers have shown that plastically bent sapphire fibers are promising for use in IR sensing and power-delivery applications.

Large-bore polystyrene-Ag-coated hollow glass waveguides with inner diameters of 3.6 mm and 8 mm had been produced for transmission of solar energy, the waveguides were fabricated by liquid phase deposition method, over 6 W focused solar radiation had been transmitted by an 8mm-thick 1m-long waveguide. Although transmission losses of the waveguides were high at the moment, they were promising for transmitting high- power solar energy after being improved.