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Background Acute Stanford type A aortic dissection (ATAAD) is a fatal disease, and rapid and effective identification of its postoperative prognostic indicators is of great significance for stratifying patient prognosis. Serum chloride (Cl-) is an important anion in the body associating with the occurrence and development of many diseases, but the relationship between serum Cl- and ATAAD is not completely clear. Objective To investigate the relationship of admission serum Cl- level with postoperative 30-day all-cause mortality and admission serum sodium (Na+) in patients with ATAAD. Methods A retrospective cohort design was adopted. Two hundred and six consecutive ATAAD patients who underwent Sun's procedure from February 2016 to December 2019 in the Fourth Hospital of Hebei Medical University were selected. All-cause death and adverse events within postoperative 30 days of patients were followed up. The clinical baseline, laboratory and intraoperative data and postoperative 30-day prognosis were compared between tertile groups of admission serum Cl-〔T1≤102 mmol/L (n=69), 102106 mmol/L (n=67) 〕. ROC curve analysis was used to measure the performance of admission serum Cl- and Na+ in predicting all-cause mortality in ATAAD, in which the area under the ROC curve (AUC), the Youden index, sensitivity, specificity, and optimal cut-off value were calculated. Multivariate Logistic regression model was used to evaluate the association between admission serum Cl- and postoperative 30-day all-cause mortality. For assessing the relationship between admission serum Cl- and Na+, postoperative 30-day all-cause mortality and cumulative survival rate were compared between ATAAD patients in four groups divided by the optimal cut-off value of admission serum Cl- (107 mmol/L) and Na+ (139 mmol/L): high Cl- and high Na+ (Cl->107 mmol/L+Na+>139 mmol/L, n=35), high Cl- and low Na+ (Cl->107 mmol/L+Na+≤139 mmol/L, n=21), low Cl- and high Na+ (Cl-≤107 mmol/L+Na+>139 mmol/L, n=41), low Cl- and low Na+ (Cl-≤ 107 mmol/L+Na+≤ 139 mmol/L, n=109). The cumulative survival curves in different Cl- groups or Cl- and Na+ groups were presented as Kaplan-Meier curves and compared by Log-rank test. Pearson correlation analysis was used to explore the correlation between serum Cl- and Na+. Then their relationship was further analyzed by age (≥ 50 and 139 mmol/L (Na+>139 mmol/L and ≤139 mmol/L), and the interaction between serum Cl- and age, sex, hypertension, smoking and drinking was examined using multiplicative interaction model. Results The AUC of admission serum Cl- for predicting postoperative 30-day all-cause mortality was 0.695 〔95%CI (0.595, 0.795), P107 mmol/L group was 3.367 times higher than that in Cl- ≤ 107 mmol/L group 〔95%CI (1.469, 9.186), P=0.005〕. Kaplan-Meier survival analysis showed that the cumulative survival rate within 30 days after surgery was lower in T3 group than that of T1 group (χ2=8.711, P=0.003) or T2 group (χ2=9.079, P=0.011). Cl->107 mmol/L group had a lower cumulative survival rate within 30 days after surgery than Cl-≤107 mmol/L group (χ2=13.326, P 0.05). But there was a certain interaction effect between admission serum Cl- and Na+ (Na+>139 mmol/L, Pinteraction =0.012) . Conclusion Admission serum Cl- associates with admission serum Na+ level in ATAAD patients. And elevated admission serum Cl- may be an independent risk factor for postoperative 30-day all-cause mortality.

BackgroundAcute aortic dissection (AAD) is more common in critically ill patients, and hyperglycemia is an adverse factor affecting the mortality of critically ill patients.ObjectiveTo investigate the correlation between admission blood glucose level and in-hospital mortality in patients with AAD.MethodsA retrospective analysis of the case data of non-diabetic AAD patients who underwent surgical treatment at the Fourth Hospital of Hebei Medical University from January 2015 to August 2020. According to admission blood glucose level, all cases were divided into: the hyperglycemia group (>7.8 mmol/L) and the normal blood glucose group (≤7.8 mmol/L) ; Cox proportional hazard modelwas used to evaluate the correlation between admission blood glucose and in-hospital mortality in AAD patients; Kaplan-Meier method was used to analyze the survival curve; ROC analysis was conducted to evaluate the predicting values of admission blood glucose for the in-hospital mortality in AAD patients; Cox regression model were performed to determine influencing factors for in-hospital mortality in AAD patients.ResultsA total of 491 AAD patients were collected including 165 (33.6%) cases in the hyperglycemia group and 326 (66.4%) cases in the normal blood glucose group. Compared to the normal glucose group, higher in-hospital mortality was found in the hyperglycemia group (19.4% vs 10.4%, χ2=4.172, P=0.006) ; In the unadjusted Cox model, the relative risk of death in the hyperglycemia group was 1.943〔95%CI (1.199, 3.150) , P=0.007〕; After adjusting for age and sex in moderately adjusted model, it was 1.900〔95%CI (1.171, 3.082) , P=0.009〕 in the hyperglycemia group compared with the normal blood glucose group; After adjusting for age, gender, hypertension, coronary heart disease, smoking, Stanford type, systolic blood pressure and diastolic blood pressure, the risk of in-hospital death in the hyperglycemia group was 1.840〔95%CI (1.124, 3.010) , P=0.015〕. The area under the ROC curve of admission blood glucose for predicting in-hospital death of AAD patients is 0.612 (0.546, 0.696) , when the admission blood glucose cut-off value was 9.4 mmol/L, the sensitivity was 37.9% and the specificity was 84.9%, respectively. The results of multivariate Cox regression model analysis showed that Stanford type A〔HR=4.277, 95%CI (1.942, 9.420) , P

In this letter, a novel algorithm is proposed to design symbol‐level waveform for dual‐functional radar‐communication (DFRC) systems with low range sidelobe. Different from current schemes design waveform at the block level, a phase response constraint is introduced at the symbol level to provide an additional degree of freedom to decrease the range sidelobe in the pulse compression procedure, which is highly desired in radar systems. In particular, the phase response at the target direction is constrained to be similar to the given reference phase, and the matching error between the designed beampattern and the desired one is minimized subject to the constant modulus constraint. Furthermore, to guarantee the quality of service for communication, constructive interference is exploited at the symbol level for each communication user. An alternating direction method of multipliers algorithm is also proposed to solve the resulting nonconvex optimization problem with tractable subproblems solved sufficiently by the manifold optimization and standard quadratic problem. Numerical simulation results demonstrate the performance of the proposed method. [ABSTRACT FROM AUTHOR]

For collocated Multiple-Input Multiple-Output (MIMO) radar, we investigate the target detection problem in Gaussian clutter with an unknown but random covariance matrix. An inverse complex Wishart distribution is chosen as prior knowledge for the random covariance matrix. We propose two detectors in the Bayesian framework based on the criteria of the Generalized Likelihood Ratio Test. The two main advantages of the proposed Bayesian detectors are as follows: (1) no training data are required; and (2) a prior knowledge about the clutter is incorporated in the decision rules to achieve detection performance gains. Numerical simulations show that the proposed Bayesian detectors outperform the current commonly used non-Bayesian counterparts, particularly when the sample number of the transmitted waveform is small. In addition, the performance of the proposed detector will decline in parameter mismatched situation.

Reports of rare but severe thrombotic events after receiving some COVID‐19 vaccines brought concerns for the possibility of vaccine‐induced coagulation abnormality. However, no study has reported the impacts of COVID‐19 vaccination on coagulation function in pregnant women. We aimed to explore whether vaccination with inactivated COVID‐19 vaccines before pregnancy was associated with coagulation changes in pregnant women. We conducted a retrospective cohort study in a tertiary‐care hospital in Shanghai, China. A total of 5166 pregnant women were included, of whom 2721 (52.7%) completed vaccination before conception. Compared with unvaccinated women, the mean serum levels of prothrombin time (PT) and fibrinogen (FIB) were lower in vaccinated women by 0.09 (β = −0.09, 95% confidence interval [CI], −0.13, −0.05) mg/L and 0.11 (β = −0.11, 95% CI, −0.15, −0.07) mg/L, and the mean D‐Dimer (D‐D) levels were higher by 0.12 (β = 0.12, 95% CI, 0.09, 0.15) mg/L. However, no significant association was observed between COVID‐19 vaccination and serum levels of activated partial thromboplastin time (APTT), fibrinogen degradation product (FDP) or thrombin time (TT). Our findings suggested that inactivated COVID‐19 vaccination before conception resulted in a small change in maternal coagulation function, but this might not have clinical significance. [ABSTRACT FROM AUTHOR]