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Objective To investigate the effect of contrast agent temperature on adverse reactions of transvaginal four‐dimensional hysterosalpingo‐contrast sonography （TVS 4D‐Hycosy） with pain as the main manifestation. Methods Double‐blind randomized controlled study. A total of 220 patients who underwent TVS 4D‐Hycosy examination were randomly assigned （1∶1） to receive preheated contrast agent （38 ℃） and normal temperature contrast agent （22 ~ 26 ℃） respectively. The Stacey scoring scale was used to comprehensively evaluate pain, nausea, vomiting and other adverse reactions and NRS scoring scale were used to evaluate pain alone, and the occurrence of adverse reactions after intrauterine catheterization and during the examination was compared between the two groups. After the inspection, compare the proportion of people with persistent pain at 0 h, < 0.5 h, < 1 h, 1 ~ 24 h, and > 24 h between the two groups. Result There was no significant difference in Stacey adverse reaction score and NRS pain score between the two groups after intrauterine catheterization （Z = 0.231, -0.341, both P > 0.05）. During the examination, the Stacey adverse reaction score and NRS pain score in the preheated group were lower than those in the room temperature group （Z = 2.906, 3.837, both P < 0.05）, and the proportion of moderate and severe adverse reactions in the preheated group was lower than that in the room temperature group （χ² = 7.502, P < 0.05）, the difference between the two groups was statistically significant. After the examination, there was no significant difference in the proportion of people with persistent pain at 0 h, < 0.5 h, < 1 h, 1 ~ 24 h, and > 24 h between the two groups （χ² = 0.141, 0.566, 0.697, 0.373, all P > 0.05）. Conclusions Thermostatic preheated contrast agent reduces adverse reactions during the TVS 4D‐Hycosy and is a simple and effective way to alleviate patient suffering. [ABSTRACT FROM AUTHOR]

[Objectives]The aim of this study was to determine the optimal angiography protocol for canine heart and pulmonary artery angiography. [Methods]The variable iohexol concentrations were tested in this study to evaluate the effects on ardiac and pulmonary angiography, while injection duration and injection rate were same for the same size dogs. Iohexol dose(I content)from 100 to 200 mg·mL-1 were used in small dogs for ardiac angiography, 200 to 300 mg·mL-1 in middle dogs and 150 to 200 mg·mL-1 in large dogs. For pulmonary angiography, iohexol concentrations were 50 to 100 mg·mL-1 in small dogs, 50 to 100 mg·mL-1 in middle dogs and 150 to 200 mg·mL-1 in large dogs. Contrast agent was injected intravenously from cephalic veins after anesthesia. Dynamic scanning project was performed to obtain time-density curve of region of interest. Scanning delay time was calculated based on the time-density curve. The time to reach 200 HU aortic sinus was designated as delay time of cardiac angiography. The time to reach the peak enhancement of pulmonary artery trunk was designated as delay time of pulmonary arteriography. Then the images were obtained by volume scanning project. The images quality obtained by different contrast schemes were evaluated quantitatively and qualitatively to determine the optimal contrast scheme. [Results]The optimum cardiac angiography conditions for small dogs were 200 mg·mL-1 of iohexol concentration, 10 mL of iohexol volume, 5 mL of saline dose and 1 mL·s-1 of injection rate. For middle dogs, the optimum conditions were 250 mg·mL-1 of iohexol concentration, 15 mL of iohexol volume, 10 mL of saline dose and 1 mL·s-1 of injection rate. For large dogs, the optimum conditions were 350 mg·mL-1 of iohexol concentration, 30 mL of iohexol volume, 20 mL of saline dose and 1 mL·s-1 of injection rate. The optimum pulmonary arteriography conditions were as follows:75 mg·mL-1 of iohexol concentration, 15 mL of iohexol volume, 15 mL of saline dose and 5 mL·s-1 of injection rate in small dogs. For middle dogs those were 100 mg·mL-1 of iohexol concentration, 20 mL of iohexol volume, 20 mL of saline dose and 5 mL·s-1 of injection rate. And for large dogs those were 175 mg·mL-1 of iohexol concentration, 30 mL of iohexol volume, 30 mL of saline dose and 5 mL·s-1 of injection rate. The higher post-vascular enhancement CT values with good image quality and good contrast effects were obtained when used above conditions. [Conclusions]Through repeated tests, the contrast agent conditions used in this test can obtain satisfactory and clinically diagnostic images and can be applied to CT imaging of cardiac and pulmonary artery diseases in dogs. [ABSTRACT FROM AUTHOR]

[Objectives] Simultaneous color contrast is a phenomenon which describes how the visual perception of a colored target can be affected by the other colors or patterns. The study of simultaneous color contrast in insects has stronger ecological relevance than studies using plain colored targets or mono-wavelength light as test stimuli, and will contribute to the optimization of colored boards for trapping insect pests. [Methods] Laboratory bioassays and field trapping experiments were used to investigate simultaneous color contrast in alate Myzus persicae by recording if these were attracted to, or repelled by, combinations of different colors. [Results] The interaction between background and target color was extremely significant. Among the 64 patterns prepared using eight saturated colors, the most preferred were saturated yellow (R=G=255, B=0) and saturated green (R=B=0, G=255). The addition of any spots of another color on a yellow or green background significantly reduced their attractiveness relative to background color alone, even when the composite patterns combined yellow and green. Moreover, the most repellent pattern was a red background with black spots, which is similar to the pattern on the elytra of common lady beetles. A series of paired tests confirmed that this repellence was a true simultaneous color contrast effect. The pattern of a black background with red spots was also significantly repellent (black background + red spot vs plain red: t9 = 13.18, P < 0.000 1; black background + red spot vs. plain black: t9 = 2.14, P = 0.061 3), but less so than the pattern resembling lady beetle elytra (t9 = 3.97, P = 0.003 3). The optimal parameters (background redness=192, spot gamma value = 0, spot diameter ≤ 2 mm) of the repellent pattern were determined using an orthogonal design experiment. The results of a field trapping experiment demonstrated that the simultaneous color contrast effect of a red background and black spots was significant when the patterns were added to a less attractive green board, but not so when the patterns were added to a highly attractive yellow board. [Conclusion] The color preferences of alate M. persicae are affected by simultaneous color contrasts. The most attractive color was plain, solid yellow, followed by plain, solid green. Composite patterns of these two colors were significantly less attractive than the corresponding plain colors. The most repellant color pattern resembled the pattern on the elytra of common lady beetles. However, results of a field bioassay indicates that alates are only repelled by this pattern when it is on a green background. [ABSTRACT FROM AUTHOR]

Objective To explore the clinical value of digital subtraction angiography (DSA) in the judgment of vascular injury in upper limb wounds repaired by anterolateral femoral flap. Methods From December 2018 to November 2019, 24 patients with upper limb wounds were repaired by free anterolateral femoral flap. The DSA was used to locate the perforating branch of anterolateral femoral flap before operation and to determine the location of anastomotic vessels by judging the vascular injury in recipient site. There were 10 cases of hand wounds, 4 cases of wrist wounds, 5 cases of forearm wounds, 4 cases of elbow wounds in and 1 case of upper limb wounds. The area of upper limb wounds ranged from 6.0 cm×4.0 cm to 20.0 cm×12.0 cm. The donor site of anterolateral femoral flap was directly sutured. Results No adverse effects of contrast agents were found in 24 patients, and all flaps survived. Two cases of flaps had vascular crisis after operation and survived after active exploration. All wounds were healed in one stage. The follow-up period was from 6 to 15 months. The texture of flap was good and the appearance was satisfactory. The sensation recovered from S2 to S3. There was linear scar in the donor site. No pain and edema were found. The function of lower limb was normal. Conclusion The vascular injury could be accurately judged by DSA examination before upper limb wounds repaired by anterolateral femoral flap. The location of anastomotic vessels could be further determined, the operative efficiency could be improved and the necrosis rate of flap was reduced. [ABSTRACT FROM AUTHOR]

In the slice images of the xylem of Caragana stenophylla Pojarkthis paper proposed a novel algorithm that combined the K-means clustering and circle structure extraction algorithm, to achieve much more accurate information data of the xylem than that from the traditional image processing algorithms. Firstly, the dynamic Butterworth homomorphic filtering can be used to compensate for illumination variations on V components in the 30 images of Caragana stenophylla Pojark xylem in a HSV color space; then the K-means clustering can be used to initially segment the a and b components of the pre-processed xylem images under the Lab color space with a cluster of 3，finally, the circle structure extraction algorithm can be used to accurately cluster and extract the specific feature of the xylem images. The processing results showed that the Butterworth homomorphic filtering have a good effect on the illumination compensation for the various illumination variations in a series of different images, indicating some high resolution information in detail, texture, contrast and visual effect of the images. After being initially segmented by K-means clustering, the illumination compensated xylem images had an average section error (R) of 5.15%, over-segmentation error (OR) of 1.48% and under-segmentation error (UR) of 6.46%, respectively, which decreased by 23.60, 7.75 and 13.01 percentage points, respectively compared to the xylem images before the illumination compensation. The segmentation accuracy was enhanced significantly, which decreased 10.43 percentage points in R, 4.58 percentage points in OR and 4.96 percentage points in UR to 3R-G-B threshold value clustering algorithm after the illumination compensation. The average mean error of the circle structure extraction for the xylem images after the initial segment reached 2.26%, which was 11.69 percentage points lower than that of the watershed method, and 4.93 percentage points lower than that of pit matching method. The average duration of the algorithm in this case was 3.66 s on each image, saving 0.95 and 4.78 s compared to that of the watershed and pit matching method, respectively. The root mean squared error (RMSE) of the algorithm was 0.52%, one third of that from the watershed and half of that from the pit matching. The proposed combined algorithm can automatically segment and extract the xylem information data from Caragana stenophylla Pojark, particularly on some images with the complex xylem structure, uneven illumination and uneven internal distribution, indicating better than the other two types of segmentation algorithms. These findings can provide fundamental reference for the promising extraction algorithm and the image processing of the xylem from other plants. [ABSTRACT FROM AUTHOR]

With the technical developments of poisioning and depth detecting, nowadays, the accuracy of sounding results is highly improved than before, while the effect of water correction still stays the same, which makes it become the main restraint for bathymetry precise. It is key to determine tidal time difference between tidal gauges in time - difference method, which is commonly used to conduct water correction. However, the influence of temporal variation of tidal time-difference on water correction is usually ignored, and the time period of observations to determine tidal time - difference is also selected freely. Focusing on these problems, the phenomenon and cause of temporal variation of tidal time-difference are analyzed from the perspective of the merging theory of tidal constituents. Daily determined and hourly determined tidal time differences are compared in value and meaning and the error formula of water correction in time-difference method is educed. Data experiments are conducted in one sea area to show the contrast effect of water correction by using daily and hourly determined time-difference of tide. The research reveals that it is more precise and reasonable to use hourly determined tidal time-difference, than to use daily determined one, which is currently utilized for water correction. [ABSTRACT FROM AUTHOR]

The suppression of random noise is an important step in the process of microseismic signal analysis. Nowadays, the most of noise reduction technologies have some problems. Owing to the stochastic non-stationarity of microseismic signal, this paper proposed a microseismic signal denoising method combined with empirical mode decomposition(EMD) and wavelet threshold denoising method to suppress random noise. The EMD can adaptively break signal down into a finite number of intrinsic mode functions(IMF) which are arranged according to the frequency from high to low order. After decomposition, the noise of microseismic signal is mainly concentrated in the higher frequency of the IMF component. Based on the principle of abrupt change of noise energy, the boundary of IMF component between high and low is found. The wavelet threshold method is used to process the high-frequency IMF. Finally, the high-frequency IMF components of denoised and the remaining low-frequency IMF components can be reconstructed to obtain the denoised microseismic signal. The simulation results show that the method can fully retain the transient non-stationarycharacteristics of the microseismic signal, and has a better denoising effect than that of the contrast method. [ABSTRACT FROM AUTHOR]

A volume effect of industrial computed tomography ( CT ) imaging and a contrast method for density inspection are used to build an algebraic model for base separation inspection, which improves the base separation inspection method in theoretical and practical ways. The size information is qualitatively and quantitatively analyzed with high precision by the fluctuation of inspected CT values. The experimental results of base separation inspection show that the density contrast model is suitable for the inspection of 0. 20 ~ 0. 50 mm base separation, and the relative error is less than 3. 5% . [ABSTRACT FROM AUTHOR]