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Surgical operation is the most commonly used method to correct intermittent exotropia(IXT), and the results are relatively positive. However, after surgery, some patients will experience a recurrence of exotropia. The recurrence rate increases with time. At present, there is no unified conclusion on the factors in the recurrence after intermittent exotropia surgery. Age at onset and surgery, preoperative and initial postoperative deviation, abnormal visual function, type of intermittent exotropia, operation pathway and preoperative assessment method may all be the risk factors. This review presents a conclusion on different results of recent studies and indication of the interaction among factors in order to gain a better understanding of the surgical indication and provide guidance for future research directions.

Objective To investigate nursing interns' self-efficacy of clinical nursing assessment skills and its influencing factors, both at the middle and the final stages of their internship, so to improve the quality of clinical teaching and students' assessment skills. Methods We used convenience sampling to enroll nursing students who completed their internship in Peking Union Medical College Hospital from January 2016 to December 2017. A self-designed questionnaire was introduced to evaluate their self-efficacy of clinical nursing assessment skills in the middle and the final stages of internship. Differences between the two stages were compared, and influencing factors were analyzed. Results Forty-five students (with junior college diploma or above) were included, with a mean age of (22.0±1.1) years. There were 9 males (18.0%), and the mean interning duration were (6.0±1.4) months in the middle stages of internship and (10.2±1.6) months in the final stage. Scores of self-efficacy at admission were similar between the middle and final stages of internship. However, students at the final stage of internship got significantly higher scores both in total and in therapeutic assessment skills than those in the middle internship stage (77.3±7.9 versus 73.5±11.0, P＜0.05; 38.9±5.9 versus 36.2±7.8,P＜0.05).Gender, age and diploma were related to scores of self-efficacy in the mid-final stage of internship (P＜0.05). Conclusions Clinical teaching played a critical role in the education of nursing students. Targeted teaching measures should be taken to promote their ability of training assessment according to the stages of their internship, their gender, age and diploma, so to further improve the quality of clinical training.

The historical evolution, the latest research progress and the related industrial status of equipment development of the three major photopolymerization-based ceramic 3D printing technologies were reviewed, i.e. stereolithography (SL), digital light processing (DLP) and two-photon polymerization (TPP). The characteristics of feedstock materials, printing process, post-treatments and final ceramic properties were summarized and discussed.Meanwhile,some of the issues and challenges such as incapability of mass production and low efficiency persist, and high-end industrial application scenarios of printed parts still need to be excavated. Therefore, new materials, new theories and new technologies regarding ceramic photopolymerization-based 3D printing should be further developed in order to seek for efficiency and application breakthroughs. Finally, it was suggested that structural-functional integral/gradient manufacturing and multi-material/multi-process comprehensive and efficient manufacturing are the important development directions of ceramic 3D printing technology in the future.

Backgrounds: Periprocedural myocardial injury (PMI) after elective percutaneous coronary intervention (PCI) significantly influences the prognosis of coronary artery disease (CAD). However, it was unclear whether the occurrence of PMI was associated with a series of controllable factors, such as PCI strategy or severity of CAD.Methods: A total of 544 consecutive stable CAD patients underwent elective PCI were enrolled. The main outcome is PMI, defined as troponin T after PCI was at least one value above the 99th percentile upper reference limit. Major adverse cardiac events (MACE), including all-cause death, repeat myocardial infarction and target vessel revascularization were record in the period of follow-up. Univariate and multivariate analysis was applied to assess predictors for the occurrence of PMI.Results: The incidence of PMI was 38.8% in the study. Compared with non-PMI patients (n = 333), PMI patients (n = 211) had more diseased vessels, higher Gensini and Syntax score. Meanwhile, there were higher incidence of MACE in PMI groups (9.5% vs. 3.2%, P < 0.01). We found that PMI patients underwent higher proportion of multi-vessel PCI simultaneously (32.2% vs. 10.5%, P < 0.01) and had more stents implanted (1.8 ± 0.8 vs. 1.4 ± 0.6, P < 0.01). Importantly, after simultaneously adjusted by other factors (such as age, diabetes, total cholesterol, number of diseased vessels, Gensini score and stent length), the risk of PMI was still increased 84% by multi-vessel PCI independently (OR = 1.654, 95% CI = 1.004-2.720, P < 0.05).Conclusions: The phenomenon of PMI occurred more commonly in stable CAD patients underwent multi-vessel PCI. Multi-vessel international therapy could increase the risk of PMI in elective PCI. [ABSTRACT FROM AUTHOR]

Backgrounds: Reduced left ventricular ejection fraction (LVEF) after acute myocardial infarction (AMI), which implies the occurrence of cardiac dysfunction, impacts cardiac prognosis, even after primary percutaneous coronary intervention (PCI). This study was designed to clarify the difference of clinical and angiographic predictors for reduced LVEF in ST-elevation myocardial infarction (STEMI) patients with left anterior descending artery (LAD) or non-LAD vessel as culprit artery.Methods: This was a retrospective study to review a total of 553 patients of STEMI underwent primary PCI in our hospital. All patients underwent echocardiography. Univariate analysis, multivariate analysis and classification and regression tree (CART) were performed between LAD related AMI and non-LAD related STEMI. The primary outcome was the occurrence of reduced LVEF 4-6 days after PCI.Results: In this study, culprit arteries of STEMI were 315 in LAD system (6 in left main artery, 309 in LAD) and 238 in non-LAD system (63 in left circumflex and 175 in right coronary artery). Compared with non-LAD group, post-MI LVEF was significantly reduced in LAD related STEMI group (52.4 ± 9.3% vs. 57.1 ± 7.8%, P < 0.01). Multivariate analysis indicated that elder (>65 years), time to hospital and proximal occlusion were associated with reduced LVEF (<55%) in LAD related STEMI patients. However, in non-LAD patients, time to hospital, multivessel stenosis and post-PCI blood pressure predicted the occurrence of reduced LVEF. Furthermore, CART analysis also obtained similar findings.Conclusions: Patients with LAD or non-LAD related STEMI could suffer reduced LVEF, while the clinical and angiographic predictors for the occurrence were different. [ABSTRACT FROM AUTHOR]

Acceleration replicate control in time domain is generally used in earthquake simulation test. To overcome the shortcoming of positive displacement amplitude in this control, an earthquake simulation control strategy based on multi-movement parameters replicate control in time domain is proposed. This control method divides the earthquake simulation frequency band into displacement-controlled zone and acceleration-controlled zone, and continual identifies the impedance of the system acceleration and displacement impedance using adaptive control, and designs synthesis method to produce shaker drive signal, and replicate the displacement and acceleration reference signals at the same time, and ultimately to achieve high-precision earthquake simulation test in the all test frequency band. The experimental results which are got in Zhejiang University shaking table indicate that this control can obtain the acceleration correlation coefficient of reference signal and control signal in time domain can reach 97% after several frames of earthquake simulation test; meanwhile can obtain higher accuracy of the displacement replication in time domain that displacement peak error of less than 5%. [ABSTRACT FROM AUTHOR]

The equations will be ill-conditioning when the polynomial order is large in the course of establishing structural frequency response function with rational fraction polynomials. To overcome the drawback a kind of improved discrete orthogonal polynomials have been proposed in fourier domain developed from relatives in real domain which not only overcomes the unnecessary computation incurred by negative frequencies but also makes the equations uncoupled. Overcoming this numerical problem has made this technique more effective. [ABSTRACT FROM AUTHOR]

Researches on road simulation control are divided into time domain replication, frequency domain replication, frequency domain and amplitude domain joint replication. Among them, the last is mainly used when the road vibration signal includes more large amplitude "spikes". The road vibration signals considered in this paper are almost smooth and less spikes, so traditional control methods used for time domain replication and frequency domain replication are analyzed. The analysis results show that the control accuracy of traditional frequency domain control method is bad in low frequencies; the control accuracy of traditional time domain control method is also influenced because it can't respond the changing of system characteristics during the testing, and the time used for testing is long when the road vibration signal lasts long time which leads to more costs in testing. Therefore an adaptive control is used for time domain replication of road simulation in this paper which avoids the problems mentioned. Finally a road simulation test was carried out and the results proved that control accuracy using this algorithm met the requirement and the time spend in road simulation testing using this algorithm was reduced. [ABSTRACT FROM AUTHOR]

BACKGROUND. Coronary MRA is commonly performed at 1.5 T using SSFP acquisitions. Coronary MRA performed at 3 T using SSFP is limited due to impaired fat suppression and has been typically investigated using contrast-enhanced techniques. A Dixon fat-water separation gradient-recalled echo (GRE) method may enable high-quality unenhanced 3-T coronary MRA. OBJECTIVE. The purpose of this study was to compare 1.5-T SSFP and 3-T Dixon water-fat separation GRE methods for unenhanced whole-heart coronary MRA in patients with suspected coronary artery disease (CAD). METHODS. This prospective study included 44 patients (27 men and 17 women; mean age, 59 ± 8 [SD] years) with an intermediate to high risk of CAD who underwent both 1.5-T SSFP and 3-T Dixon GRE coronary MRA examinations before undergoing coronary angiography (CAG). Two radiologists independently assessed coronary arteries in terms of subjective image quality (on a scale of 1-5, with 5 denoting the highest image quality), number of visible segments, apparent contrast-to-noise ratio (CNR; vs myocardium), and presence of significant stenoses. Methods were compared using the mean of the readers' values for apparent CNR and using consensus interpretations for other measures. CAG served as the reference standard for detecting the presence of stenoses. RESULTS. Expressed as a kappa coefficient, interobserver agreement was 0.85 for image quality, 0.85 for segment visibility, and 0.83 for stenosis, and expressed as an intraclass correlation coefficient, interobserver agreement was 0.92 for apparent CNR. The mean overall image quality score was 4.0 ± 1.1 for 3-T Dixon GRE versus 3.0 ± 1.2 for 1.5-T SSFP. The percentage of visible segments for 3-T Dixon GRE versus 1.5-T SSFP was 96.7% versus 88.9% for all segments, 96.9% versus 90.1% for distal segments, and 93.1% versus 77.2% for branch segments. The mean overall apparent CNR was 93.2 ± 29.2 for 3-T Dixon GRE versus 80.8 ± 27.9 for 1.5-T SSFP. The 3-T Dixon GRE method, compared with the 1.5-T SSFP method, showed higher sensitivity and specificity in per-vessel analysis (87.9% vs 77.3% and 83.3% vs 60.6%, respectively), per-segment analysis (84.6% vs 74.8% and 90.9% vs 79.6%, respectively), and per-segment analysis of distal and branch segments (89.7% vs 75.9% and 89.7% vs 73.7%, respectively). CONCLUSION. For unenhanced coronary MRA, 3-T unenhanced Dixon GRE had better image quality and diagnostic performance than 1.5-T SSFP, particularly for distal and branch segments. CLINICAL IMPACT. The 3-T Dixon GRE technique may be preferred to the current clinical standard of the 1.5-T SSFP technique for unenhanced coronary MRA.

Objective: Aortic valve calcification (AVC) is common in the elderly and associated with increased cardiovascular mortality, while diabetes is one of the confirmed risk factors for coronary artery disease (CAD). In this study, we aimed to evaluate the prevalence and severity of CAD in type-2 diabetic patients with AVC., Methods: From June to December in 2007, a total of 325 consecutive patients with chest pain or chest distress were admitted for coronary angiography. The severity of CAD was evaluated by the Gensini score and the number of stenosed vessels. All patients underwent transthoracic echocardiography for detecting AVC., Results: Compared with the patients without diabetes (n = 221), the type-2 diabetic patients (n = 104) had a similar prevalence of CAD (66.5% vs. 72.1%, P = 0.312). Further classified by the presence of AVC, patients with AVC had a higher prevalence of CAD, average Gensini score and the number of stenosed vessels, both in the group with and without diabetes. It was also demonstrated that the odds ratio (OR) of AVC for CAD in the diabetic patients was higher than in the non-diabetic ones (3.405 vs 2.515) after chi-square analysis (single-variable). However, at multivariable logistic regression analysis for CAD, the OR of AVC was 3.757 (P = 0.03) in diabetic group, while it did not achieve statistical significance in the non-diabetic group (OR = 2.130, P= 0.074)., Conclusions: Type-2 diabetic patients with AVC had a higher prevalence of and more severe CAD.