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Remaining useful life (RUL) prediction in real operating environment (ROE) plays an important role in condition-based maintenance. However, the life information in ROE is limited, especially for some long-life products. In such cases, accelerated degradation test (ADT) is an effective method to collect data and then the accelerated degradation data are converted to normal level of accelerated stresses through acceleration factors. However, the stresses in ROE are different from normal stresses since there are some other stresses except normal stresses, which cannot be accelerated, but still have impact on the degradation. To predict the RUL in ROE, a nonlinear Wiener degradation model is proposed based on failure mechanism invariant principle which is the precondition and requirement of an ADT and a calibration factor is introduced to calibrate the difference between ROE and normal stresses. Moreover, the unit-to-unit variability is considered in the concern model. Based upon the proposed approach, the RUL distribution is derived in closed form. The unknown parameters in the model are obtained by a new two-step method through fuzing converted degradation data in normal stresses and degradation data in ROE. Finally, the validity of the proposed model is demonstrated through several simulation data and a case study.

The diffusion coefficients are often assumed irrelevant to stresses in Wiener degradation process. However, there is evidence that the diffusion coefficients under different accelerated stress leve...

To observe the effect of transcutaneous electric acupoints stimulation (TEAS) on vascular endothelial function and inflammatory factors after percutaneous coronary intervention (PCI) in patients.A total of 94 patients with coronary heart disease and undergoing PCI were randomized into a TEAS group and a sham-TEAS group, 47 cases in each one. In the TEAS group, TEAS started at unilateral Neiguan (PC6) and Ximen (PC4) 30 min before PCI till the end of PCI. In the sham-TEAS group, the procedure and persistent time were same as the TEAS group, but no electric stimulation was performed. Before treatment and at 8 h and 24 h after PCI, the levels of serum endothelin-1 (ET-1), von Willebrand factor (vWF), nitric oxide (NO), blood flow dependent diastolic function (FMD), interleukin-6 (IL-6), inteleukin-10 (IL-10), matrix metalloproteinase-9 (MMP-9) and high-sensitivity C-reactive protein (hs-CRP) were detected in the patients successively.Compared with the levels before PCI, the levels of ET-1 and vWF were all increased at 8 h and 24 h after PCI in the two groups (TEAS effectively improves the vascular endothelial function and reduces serum inflammatory factors after PCI.

To observe the prevention effect of transcutaneous electrical acupoint stimulation (TEAS) for chemotherapy-related myelosuppression in non-small cell lung cancer.A total of 102 patients with non-small cell lung cancer who received initial chemotherapy were randomly divided into a conventional group, a medication group and a TEAS group, 34 cases in each one. The conventional group was treated with chemotherapy of gemcitabine combined with cisplatin and given routine care. On the basis of conventional group's treatment, the medication group was givenCompared with before chemotherapy, the leukocyte counts of three groups were decreased at various time points after chemotherapy (Transcutaneous electrical acupoint stimulation can prevent chemotherapy-induced myelosuppression (leukocyte, platelets) in patients with non-small cell lung cancer and improve patient comfort situation.

Objective: To explore the clinical characteristics and etiology of bacterial meningitis (BM) in Chinese children. Method: BM cases in children 28 days to 18 years old were collected from January 2014–December 2016 and screened according to World Health Organization standards. Clinical features, pathogens, and resistance patterns were analyzed. Results: Overall, 837 cases were classified into five age groups: 28 days–2 months (17.0%), 3–11 months (27.8%), 12–35 months (24.0%), 3–6 years (13.9%), and >6 years (17.3%). Major pathogens were Streptococcus pneumoniae (S. pneumoniae, n = 136, 46.9%), group B Streptococcus (GBS, n = 29, 10.0%), and Escherichia coli (E. coli, n = 23, 7.9%). In infants 3 months old, S. pneumoniae (54.7%), which had a penicillin non-susceptibility rate of 55.4% (36/65), was most frequent. The resistance rates of S. pneumoniae and E. coli to cefotaxime and ceftriaxone were 14.0%/40.0% and 11.3%/68.4%, respectively. All GBS isolates were sensitive to penicillin. Conclusions: The occurrence of BM peaked in the first year of life, while S. pneumoniae was the predominant pathogen in children >3 months of old. The antibiotic resistance of S. pneumoniae was a concern. Keywords: Bacterial meningitis, Children, Pathogen, Antibiotic susceptibility