Design and Experimental Study of Shape Memory Alloy and Piezoelectric Composite Power Generation Device.

In order to solve the problem of ineffective utilization of waste heat generated by energy consumption in industrial production and life, a low-frequency thermal energy conversion type piezoelectric energy trap is proposed, and relevant theoretical analysis and experimental research are conducted. The device utilizes a piezoelectric film (polyvinylidene fluoride) combined with a shape memory alloy and features a simple green structure that can supply energy to microelectronic devices. First, the structural design and working principle of the device are analyzed and the dynamics model is built. Second, COMSOL Multiphysics simulation software (Version 5.6) is used to analyze and calculate the output voltage of shape memory alloy shrinkage, piezoelectric film shape and parameters. Finally, the experimental prototype is machined and fabricated by the fine engraving machine, and the experimental platform is built for relevant performance tests. The experimental results show that when the temperature is 100 °C, the maximum strain of shape memory alloy with 1 mm diameter is 0.148 mm. When the shape of the piezoelectric film is triangular, the length of the bottom edge is equal to the height of the triangle and the thickness ratio is 0.5, the maximum output voltage is 2.12 V. The experimental results verify the feasibility of the designed device and provide new ideas for subsequent research on piezoelectric energy capture.

Primary borderline mucinous tumor of the testis with postoperative metastasis: A rare case report.

Primary borderline mucinous tumor of the testis is extremely rare and belongs to the ovarian epithelial type. Testicular borderline mucinous tumor is intermediate in malignancy between benign mucinous cystadenoma and mucinous carcinoma, and their clinical treatment is mainly based on radical testicular resection. The reported cases with PBMTs have a good prognosis with no cases of recurrence or metastasis after surgery reported. However, we herein report a 21-year-old male who may be the first reported case of PBMT of the testis with postoperative tumor metastasis.

Contrast-enhanced ultrasound in association with serum biomarkers for differentiating combined hepatocellular-cholangiocarcinoma from hepatocellular carcinoma and intrahepatic cholangiocarcinoma.

BACKGROUND: Combined hepatocellular-cholangiocarcinoma (CHC) is a rare type of primary liver cancer. Due to its complex histopathological characteristics, the imaging features of CHC can overlap with those of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). AIM: To investigate the possibility and efficacy of differentiating CHC from HCC and ICC by using contrast-enhanced ultrasound (CEUS) Liver Imaging Reporting and Data System (LI-RADS) and tumor biomarkers. METHODS: Between January 2016 and December 2019, patients with histologically confirmed CHC, ICC and HCC with chronic liver disease were enrolled. The diagnostic formula for CHC was as follows: (1) LR-5 or LR-M with elevated alpha-fetoprotein (AFP) and carbohydrate antigen 19-9 (CA19-9); (2) LR-M with elevated AFP and normal CA19-9; or (3) LR-5 with elevated CA19-9 and normal AFP. The sensitivity, specificity, accuracy and area under the receiver operating characteristic curve were calculated to determine the diagnostic value of the criteria. RESULTS: After propensity score matching, 134 patients (mean age of 51.4 ± 9.4 years, 108 men) were enrolled, including 35 CHC, 29 ICC and 70 HCC patients. Based on CEUS LI-RADS classification, 74.3% (26/35) and 25.7% (9/35) of CHC lesions were assessed as LR-M and LR-5, respectively. The rates of elevated AFP and CA19-9 in CHC patients were 51.4% and 11.4%, respectively, and simultaneous elevations of AFP and CA19-9 were found in 8.6% (3/35) of CHC patients. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy and area under the receiver operating characteristic curve of the aforementioned diagnostic criteria for discriminating CHC from HCC and ICC were 40.0%, 89.9%, 58.3%, 80.9%, 76.9% and 0.649, respectively. When considering the reported prevalence of CHC (0.4%-14.2%), the positive predictive value and NPV were revised to 1.6%-39.6% and 90.1%-99.7%, respectively. CONCLUSION: CHCs are more likely to be classified as LR-M than LR-5 by CEUS LI-RADS. The combination of the CEUS LI-RADS classification with serum tumor markers shows high specificity but low sensitivity for the diagnosis of CHC. Moreover, CHC could be confidently excluded with high NPV.

[Ultrasound Manifestations of Eyes of Pediatric Patients with Morning Glory Syndrome].

OBJECTIVE: To analyze ultrasonic manifestations of eyes of pediatric patients with morning glory syndrome (MGS). METHODS: Clinical data and ultrasound (US) findings for six children (4 males and 2 females, 5-60 months old) diagnosed with MGS between 2005 and 2016 were reviewed. RESULTS: Of the 12 eyes, seven were diagnosed with MGS; one with cataract; the other four were normal. One child had both eyes diagnosed with MGS. Of the seven eyes with MGS (5 right, 2 left), one was small associated with persistent hyperplastic primary vitreous (PHPV); 2 had retinal detachment. Findings of high frequency ultrasound included local anechoic lesions with distinct boundary showing a convert bottle-neck shape that appeared in the area of optic disk of posterior pole. The lesions communicated with the vitreous caicy and extended to the optic nerves. The lesions had a maximum depth of 4-15 mm [(8.29±4.42) mm] and a maximum width of 4-11 mm [(6.86±2.67) mm]. Hypoecho material was found in the bottom of five of the seven lesions. The distance between the end of the optic nerves and the bottom of the lesions ranged from 0 to 4.5 mm. Lower levels (Adler 0-1 grade) of blood flow in the bottom of the lesions were found compared with those (3-5 grade) in the rim of the lesions. CONCLUSION: MGS is rare and usual occurs in young children, especially infants. It is often associated with various eye complications. The ultrasound manifestations of MGS are characterized with a local anechoic lesion mimicking a convert bottle-neck shape in the area of optic disk of posterior pole.

[Application of high frequency color Doppler ultrasound in anterolateral thigh flap surgery].

OBJECTIVE: To investigate the effectiveness of high frequency color Doppler ultrasound for detecting perforators in the anterolateral thigh (ALT) flap surgery. METHODS: Between February 2011 and July 2012, 8 patients underwent high frequency color Doppler ultrasound to detect the perforator anatomy before ALT flap surgery. There were 5 males and 3 females, aged 21-46 years (mean, 34 years). Defects were caused by excision of squamous cell carcinoma in 2 cases, by scalp avulsion in 2 cases, by soft tissue necrosis after neck trauma in 1 case, by excision of groin fibrosarcoma in 1 case, by excision of groin melanoma in 1 case, and by malformation of the face in 1 case. The defect size varied from 12 cm x 7 cm to 22 cm x 18 cm. The perforator with wider caliber, faster flow speed, and shorter intramuscular trajectory was selected, and the flap was designed according to the observed results, which size varied from 14 cm x 9 cm to 25 cm x 20 cm. The donnor sites were repaired by free skin graft. RESULTS: Totally, 19 perforators in the flap area were detected by high frequency color Doppler ultrasound, and 18 were identified during operation, with an accuracy rate of 94.7%. The point going out muscle, the travel and direction of perforators observed during operation were basically in accordance with those detected by high frequency color Doppler ultrasound. The other flaps survived, and obtained healing by first intention except 1 flap which had partial fat necrosis with healing by second intention. The skin graft at donor site survived. All patients followed up 4-16 months (mean, 8 months). The flaps had good color and texture. CONCLUSION: High frequency color Doppler ultrasound is a valuable imaging modality for the preoperative assessment of the vascular supply for ALT flap.

Multimodal preoperative evaluation system in surgical decision making for rectal cancer: a randomized controlled trial.

PURPOSE: Multimodal preoperative evaluation (MPE) is a novel strategy for surgical decision making, incorporating the transrectal ultrasound (TRUS), 64 multi-slice spiral computer tomography (MSCT), and serum amyloid A protein (SAA) for rectal cancer. This trial aims to determine the accuracy of MPE in preoperative staging and its role in surgical decision making for rectal cancer. METHODS: Two hundred twenty-five participants with histologically proven rectal cancer with tumor height less than 10 cm were randomly assigned into three arms in the ratio 1:1:1. Arm A (MPE) was multimodal staged by the combination of MSCT, TRUS, and SAA. Arm B (MSCT+SAA) was staged by MSCT and SAA. Arm C (MSCT) was staged only by MSCT. The primary endpoints were the accuracy of preoperative staging and expected surgical procedures. This study is registered as an International Standard Randomised Controlled Trial, number ChiCTR-DT-00000409. RESULTS: The analysis showed statistical difference in the accuracy of T staging between arm A and B (94.6% vs. 77.8%, P=0.003) and arm A and C (94.6% vs. 80.6%, P=0.010). Statistical difference was also observed between the accuracies of preoperative N staging between arm A and C (85.1% vs. 69.4%, P=0.023) and arm A and B (85.1% vs. 84.7%, P=0.029). Surgical decision making in arm A was more accurate than that in arm C (95.9% vs. 80.6%, P=0.001). Pathological T stage (P<0.001), N stage (P<0.001), tumor node metastasis stage (P<0.001), serum level of SAA (P=0.002), and tumor height (P=0.030) were significantly associated with final surgical procedures. CONCLUSION: MPE is an effective strategy in preoperative staging and more accurate than other available strategies in surgical decision making for rectal cancer.