The impeller, as a key component of artificial heart pumps, experiences high shear stress due to its rapid rotation, which may lead to hemolysis. To enhance the hemolytic performance of artificial heart pumps and identify the optimal combination of blade parameters, an optimization design for existing pump blades is conducted. The number of blades, outlet angle, and blade thickness were selected as design variables, with the maximum shear stress within the pump serving as the optimization objective. A back propagation (BP) neural network prediction model was established using existing simulation data, and a grey wolf optimization algorithm was employed to optimize the blade parameters. The results indicated that the optimized blade parameters consisted of 7 impeller blades, an outlet angle of 25 °, and a blade thickness of 1.2 mm; this configuration achieved a maximum shear stress value of 377 Pa-representing a reduction of 16% compared to the original model. Simulation analysis revealed that in comparison to the original model, regions with high shear stress at locations such as the outer edge, root, and base significantly decreased following optimization efforts, thus leading to marked improvements in hemolytic performance. The coupling algorithm employed in this study has significantly reduced the workload associated with modeling and simulation, while also enhancing the performance of optimization objectives. Compared to traditional optimization algorithms, it demonstrates distinct advantages, thereby providing a novel approach for investigating parameter optimization issues related to centrifugal artificial heart pumps.
Neural Networks, Computer ; Algorithms ; Heart-Assist Devices ; Hemolysis ; Humans ; Equipment Design ; Stress, Mechanical ; Computer Simulation

【Objective】 To compare the value of CT pulmonary angiography (CTPA) and echocardiography in predicting the degree pulmonary hypertension (PH). 【Methods】 Fifty-four patients in our hospital who underwent right heart catheterization, CTPA and echocardiography for suspected or confirmed PH from November 2013 to April 2021 were retrospectively recruited. Pulmonary artery systolic pressure (PASP) and mean pulmonary artery pressure (PAMP) were measured by right heart catheterization. According to PAMP, the patients were divided into non-PH group and mild, moderate, and severe PH groups. The three-dimensional model of the pulmonary artery was obtained by computer-aided segmentation, and the best fitting circle diameter (Dfit), inscribed circle diameter (Dmin), circumscribed circle diameter (Dmax), hydraulic diameter (Dh), cross-sectional area (Area), circumference (Scf), and the largest area and largest short diameter of the right ventricle were measured. Echocardiography was used to estimate PASP. The differences in the above parameters between different PH groups were compared, the correlations of the above parameters with PASP and PAMP were analyzed, and statistically significant indicators were included to establish three predictive models of PAMP (Model 1: CTPA pulmonary artery; Model 2: CTPA pulmonary artery+CTPA right ventricle; Model 3: CTPA pulmonary artery+CTPA right ventricle+echocardiography), and receiver operating characteristic (ROC) curves were used to compare the diagnostic performance of the three models. 【Results】 Some parameters of main pulmonary artery (Dfit, Dmin, Dmax, Dh, Area, Scf), right pulmonary artery (Dmax, Dh, Area, Scf), left pulmonary artery (Dfit), and right ventricular short diameter increased with the increase of PAMP (P<0.05). Dfit, Dmin, Dh, and area of main pulmonary artery, right pulmonary artery and left pulmonary artery were positively correlated with PASP and PAMP (P<0.05). Right ventricular short diameter and right ventricular maximum area were positively correlated with PASP (P<0.05), and right ventricular short diameter was positively correlated with PAMP (P<0.05). The estimated value of pulmonary artery systolic blood pressure in echocardiography was positively correlated with PASP and PAMP (P<0.05). Model 1, Model 2 and Model 3 could all be used to identify mild PH and moderate PH, among which Model 3 had the best performance in identifying non-PH and mild PH, moderate PH and severe PH. 【Conclusion】 CTPA and echocardiography are helpful in assessing the degree of PH, and the combination of the two has better accuracy in distinguishing non-PH from mild PH, moderate and severe PH.

The widespread application of next generation sequencing (NGS) in clinical settings has enabled testing, diagnosis, treatment and prevention of genetic diseases. However, many issues have arisen in the meanwhile. One of the most pressing issues is the lack of standards for reporting genetic test results across different service providers. The First Forum on Standards and Specifications for Clinical Genetic Testing was held to address the issue in Shenzhen, China, on October 28, 2017. Participants, including geneticists, clinicians, and representatives of genetic testing service providers, discussed problems of clinical genetic testing services across in China and shared opinions on principles, challenges, and standards for reporting clinical genetic test results. Here we summarize expert opinions presented at the seminar and report the consensus, which will serve as a basis for the development of standards and guidelines for reporting of clinical genetic testing results, in order to promote the standardization and regulation of genetic testing services in China.

Objective To compare the diagnostic efficiency of the thyroid imaging reporting and data system (TIRADS), the Bethesda system for reporting thyroid cytopathology(BSRTC) and BRAFV600E detection, and their combined use in the differentiation between benign and malignant thyroid nodules. Methods One hundred and twenty eight patients with 128 thyroid nodules who were scheduled for ultrasound-guided fine-needle aspiration biopsy (FNAB) were recruited for the study. All of them underwent ultrasound, fine-needle aspiration cytology(FNAC) examination, and BRAFV600E detection. TIRADS and BSRTC systems were adopted to judge the ultrasound and FNAC results. The receiver operating characteristic curve was established to assess the diagnostic value of each method. Results The sensitivity, specificity, and AUC of TIRADS were 74. 3%, 84. 5%, and 0. 794, respectively. BSRTC had higher specificity(98. 3%) and equal sensitivity compared to TIRADS. The sensitivity, specificity, and AUC of BRAFV600E detection were the highest ones among the three methods. Combinations of different methods could increase the diagnostic sensitivity and accuracy. The combination of FNAC and BRAFV600E detection significantly increased the diagnostic efficiency(AUC=0. 984), with sensitivity 98. 6% and specificity 98. 3%. Conclusions The diagnostic value of BRAFV600E detection in the differentiation of benign and malignant thyroid nodules is better than both TIRADS and BSRTC, and the combination of FNAC and BRAFV600E detection reaches the best diagnostic efficiency.

Objective To investigate pulmonary function of tidal respiration in late premature infants with non-mechanical ventilation treatment at corrected gestational age of full term. Methods A total of 26 late premature infants with non-mechanical ventilation treatment at corrected gestational age of full term were collected from Qingdao Women and Children′s Hospital between April and December 2013,and saved as the late premature infant group. Also, a total of 31 full term infants with hyperbilirubinemia or neonatal ABO hemolytic disease were recruited and treated as the full term group. Then the parameters of pulmonary func-tion of tidal respiration were compared between the two groups. The late premature infant group was equally allocated into extrauterine growth retardation and non-extrauterine growth retardation groups according to the increase in weight and the ratio of time to peak tidal expiratory flow and total expiratory time(TPEF/TE) and the ratio of expiratory volume at peak tidal expiratory flow and total expiratory volume( VPEF/VE) were respectively compared in these two groups. Another correlation analysis between body weight and TPEF/TE was carried out in the non-extrauterine growth retardation group. Results (1)Gestational age difference had no significant significance between late premature infant group and full term group ( P <0. 05 ) . The body weight[(2. 39 ± 0. 44)kg vs. (3. 21 ± 0. 43) kg] and height[(46. 51 ± 3. 22) cm vs. (50. 16 ± 2. 14) cm] in late premature infant group were still lag behind that in full term group and the difference had significant significance(P<0. 05,respectively). (2)The comparison of parameters of pulmonary function of tidal respi-ration:the TPEF/TE [ ( 41. 74 ± 10. 94 )% vs. ( 48. 17 ± 11. 79 )%] , VPEF/VE [ ( 42. 66 ± 9. 66 )% vs. (48. 31 ± 9. 94)%],VPEF[(8. 02 ± 2. 85) ml vs. (10. 23 ± 3. 56) ml] and minute ventilation[(0. 76 ± 0. 23) L/min vs. (1. 00 ± 0. 44) L/min] in late premature infant group were significantly lower than those in full term group(P<0. 05,respectively). (3)The TPEF/TE and VPEF/VE all had significant significance in both late premature infant group and full term group(late premature infant group:r=0. 958,P=0. 000; full term group:r=0. 950,P=0. 000). (4)The TPEF/TE and VPEF/VE in non-extrauterine growth retardation group were closer to those in full term group. The TPEF/TE and VPEF/VE in extrauterine growth retardation group were lower than those in non-extrauterine growth retardation group(t= -2. 775,-2. 109,P=0. 011, 0. 047). Conclusion Airway(especially small airway) resistance of late preterm infant group is higher than that of term infants. Extrauterine growth retardation influences the airway(especially small airway) resist-ance.