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Thermoelectric material (TEM) is a promising candidate for power generation and cooler. Temperatures of the heat source and the cooling device usually vary with time. This article analyzes the axial vibration and strength failure of the temperature-dependent TEM subjected to time-varying thermal loadings. Temperature applying at the hot side of the TEM contains an average part and a time-dependent perturbation part. Numerical solutions of the axial force, the displacement and electric power output of the vibrating thermoelectric material are given. Based on the criterion of the maximum stress, the critical average temperature of strength failure of the thermoelectric material is presented. It is found that a bigger damping ratio results in a smaller value of the maximum displacement and axial force. The axial force is approximately proportional to the thermal loading. The axial force increases from zero to a constant with the contact stiffness of between TEMs and the boundary. The critical average temperature decreases with the contact stiffness. [ABSTRACT FROM AUTHOR]

Based on the surface piezoelectricity model, surface effects on the scattering behaviors of plane compressional waves by an embedded piezoelectric cylinder with nanoscale radius are investigated. The existence of surface stresses and surface electric displacements exerting on the boundary conditions is taken into account through generalized Young-Laplace equations, and the potential function method is employed to derive the analytical expressions of wave fields and electric potential. For two typical incident frequencies, the influence of surface properties on the distribution of electroelastic fields around the cylinder is discussed in detail. In comparison with the results obtained from the classical continuum theories, it is found that the surface effects play a prominent role on the dynamic stress and electric field concentrations, especially under a high-frequency excitation. [ABSTRACT FROM AUTHOR]

The surfaces/interfaces effect is vital in nanocomposites. The electro-elastic surface/interface theory is introduced to predict the size-dependent effective elastic constants of piezoelectric composites with spherically anisotropy nano-particles under external uniform strain, and the analytical solution is obtained. New boundary conditions governing the surface piezoelectricity are used to analyze the surface piezoelectricity effect. The average electro-elastic coupling field of the randomly distributed nano-particles with surface/interface effect is derived by using the effective field method. In the numerical examples, the interface effect under different material constituents is analyzed. It is found that the interface effect on the effective elastic constants is significantly related to the material properties of nano-particles. The elastic constants and piezoelectric constants show different effects on the effective elastic constants. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Continued EGFRTKIs treatment is still controversial for NSCLC patients with activating EGFR mutations, who acquire resistance to the drug. Of these patients, elderly ones were worth to be investigated to further examine efficacy of continued EGFR-TKIs treatment. PATIENTS AND METHODS: A total of 232 NSCLC patients (≥70-year-old) were recruited from the Chinese People’s Liberation Army General Hospital between January 1, 2009, and July 31, 2014. And 44 patients were qualified for further retrospectively investigated, which were divided into dramatic and non-dramatic progression groups based on the characteristics of progression during first-line EGFR-TKIs treatment. And they were also divided into two groups: continued EGFR-TKIs group and discontinued EGFR-TKIs group. Subsequently, progressionfree survival (PFS), post-progression survival (PPS), and overall survival (OS) of these groups were investigated by multivariate analysis. RESULTS: Median OS (28.9 months vs. 23.2 months, p = 0.46) and median PPS (16.9 months vs. 4.4 months, p = 0.216) were both not significantly different between continued EGFR-TKIs groups and discontinued ones. However, when focusing on patients with non-dramatic progression, the median OS (29.0 months vs. 23.2 months, p = 0.039) and median PPS (21.3 months vs. 3.9 months, p = 0.001) were significantly longer in the continued EGFR-TKIs patients than discontinued ones. DISCUSSION: Continued EGFR-TKIs beyond PD may be a good option for elderly patients with non-dramatic progression. The characteristic of progression after first-line EGFR-TKIs treatment should be taken into account to determine which part of patients is suitable for continued EGFR-TKIs treatment, especially for the speed of progression. CONCLUSION: Continued EGFR-TKIs treatment promotes the survival of elderly patients with acquired resistance to EGFR-TKIs therapy. [ABSTRACT FROM AUTHOR]

Hybrid halide perovskites represent one of the most promising solutions toward the fabrication of all solid nanostructured solar cells, with improved efficiency and long-term stability. This article aims at investigating the properties of CH3NH3PbI3 with controlled loading time in CH3NH3I solution via a two-step sequential deposition and correlating them with their photovoltaic performances. It is found that the optimum PCE of the loading time in the CH3NH3I solution is possible only at a relatively short time (10 min). Prolonging the loading time will degrade the perovskite film, and deteriorate the device performance by introducing a large amount of excessive defects and recombination. However, even if the material band gap remains substantially unchanged, a suitable loading time can dramatically improve the charge transport within the perovskite layer, exhibiting the out-standing performances of meso-superstructured solar cells. [ABSTRACT FROM AUTHOR]

Objective: To investigate the application effect of augmented reality and mixed reality navigation technology in three-dimensional(3D) laparoscopic narrow right hepatectomy(LRH). Methods: A retrospective analysis was performed on the clinical data of 5 patients with hepatic malignancy admitted to the First Department of Hepatobiliary Surgery,Zhujiang Hospital,Southern Medical University from September 2020 to June 2021,all of whom were males,aged from 42 to 74 years.Preoperative evaluation was performed using the self-developed 3D abdominal medical image visualization system; if all the 5 patients were to receive right hemihepatectomy,the remnant liver volume would be insufficient,so LRH were planned.During the operation,the independently developed 3D laparoscopic augmented reality and mixed reality surgical navigation system was used to perform real-time multi-modal image fusion and interaction between the preoperative 3D model and 3D laparoscopic scene.Meanwhile,intraoperative ultrasound assisted indocyanine green fluorescence was used to determine the surgical path.In this way,the LRH under the guidance of augmented reality and mixed reality navigation was completed.The predicted liver resection volume was evaluated before surgery,actual resected liver volume,surgical indicators and postoperative complications were analyzed. Results: All the 5 patients completed LRH under the guidance of augmented reality and mixed reality navigation technology,with no conversion to laparotomy.The median operative time was 300 minutes(range:270 to 360 minutes),no intraoperative blood transfusion was performed,and the median postoperative hospital stay was 8 days(range:7 to 9 days).There were no perioperative deaths,or postoperative complications such as liver failure,bleeding,or biliary fistula. Conclusion: For patients who need to undergo LRH,the use of augmented and mixed reality navigation technology can safely and effectively guide the implementation of surgery,retain more functional liver volume,improve surgical safety,and reduce postoperative complications.

Objective: To compare the operation time, estimated blood loss, clinical outcome and correction of lumbar lordosis between oblique lateral interbody fusion (OLIF) and transforaminal lumbar interbody fusion (TLIF) in patients with degenerative lumbar diseases. Methods: Seventy-three patients who underwent OLIF or TLIF surgery from January 2016 to December 2017 in Sir Run Run Shaw Hospital Zhejiang University were analyzed in this retrospective case-control study. The patients included 31 males and 42 females, with a mean age of 65.8 years (range, 36-88 years). Of the patients, there were 9 cases of calcified disc herniation, 34 cases of spinal stenosis, 17 cases of degenerative spondylolithesis, 12 cases of degenerative scoliosis and 1 case of isthmic spondylolithesis. According to the type of surgery, patients were divided into OLIF group (34 cases) and TLIF group (39 cases). The operation time, estimated blood loss and transfusion were recorded, pre-and post-operative visual analogue scale (VAS) for back pain and Oswestry Disability Index (ODI) were evaluated, and pre- and post-operative lumbar lordosis (LL) and fused segment lordosis (FSL) were measured. Student t test were used in comparison between groups. Results: Ten (29.4%) patients in OLIF group and all 39 (100%) patients in TLIF group were supplemented with posterior instrumentation (χ(2)=41.013, P <0.05). The average operation time and estimated blood loss was significantly lower in OLIF group than in those in TLIF group[(163±68) vs (233±79) min, (116±148) vs (434±201) ml, t =4.019, 6.964, both P <0.05]. There was no significant differences in decreases value in VAS and ODI after surgery between the two groups ( t =1.716, 0.522, both P >0.05). The correction of LL was 4.0°±10.0° in the OLIF group and 4.2°±6.1° in the TLIF group; the correction of FSL was 4.1°±7.0° in the OLIF group and 5.2°±4.6° in the TLIF group, with no significant differences between the two groups too ( t =0.139, 0.805, both P >0.05). The correction of LL was significantly higher in OLIF group with posterior instrumentation than that in TLIF group (9.9°±11.1° vs 4.2°±6.1°, t =2.180, P <0.05). Conclusions: Both OLIF and TLIF can restore LL to some extent, but OLIF has obvious advantages in the operation time and blood loss during surgery. When supplemented with posterior instrumentation, OLIF can achieve better correction of LL than TLIF.

Objective: To evaluate the effectiveness of mumps prevention and control after implementation of two doses mumps-containing combined vaccine (MuCV) policy by analyzing epidemiological characteristics of mumps and mumps antibody levels in general population. Methods: We obtained data on cases of mumps reported during 2004-2015 from National Notifiable Diseases Reporting System (NNDRS). Descriptive analysis methods were used to describe the epidemiological characteristics of mumps during 2004-2015. MuCV immunization information from 2005 to 2015 was obtained from the immunization information management system in Shandong Province. Antibody data of mumps in healthy people were from a cross-sectional survey according to the principle of stratified random sampling from 0 to 60 years old healthy people in 2015. Commercial ELISA kits were used to detect and quantify human IgG antibodies against mumps virus in sera, and the results were analyzed statistically. Results: The average incidence of mumps from 2004 to 2015 was 11.43/100 000 in Shandong. The incidence of mumps in the central region (14.64/100 000) was higher than that in the eastern and western regions (11.14/100 000, 11.33/100 000). The incidence of mumps was still high in 2009-2013 (stage of one-dose MuCV free, 16.07/100 000) with the highest incidence of 25.33/100 000 and 24.45/100 000 occurred in 2012 and 2013 and the cases were mainly 6 to 9 years old group (172.67/100 000). Since the second dose MuCV was introduced into NIP for 6 years old children in May 2013 in Shandong, the incidence of mump decreased significantly in 2014-2015 (7.81/100 000), especially in children of 6-8 years old who were vaccinated with two doses of MuCV (2009-2013 was 114.02/100 000; 2014-2015 was 45.66/100 000) and lower than 3-5 years old vaccinated one doses of MuCV. A total of 1 785 serum samples were collected from the healthy population, the average seroprevalence was 80.62% and Geometric Mean Concentration (GMC) was 38.11 IU/ml (95 %CI : 37.03-39.19 IU/ml) . There was no significant difference about seroprevalence in different regions, while the GMC in middle region was significantly higher compared to east and west region. The prevalence and GMC in children aged 19 months-2 years and 3-5 years old who received one dose of MuCV were significantly higher than those of <19 months old children. The GMC (46.88 IU/ml, 95 %CI: 39.43-55.74 IU/ml) in children aged 6-9 years old who received the two doses MuCV was significantly higher than that of aged 3-5 years old children (31.71 IU/ml, 95 %CI: 27.23-36.93 IU/ml). Conclusion: The incidence of mumps in Shandong was still at a high level in spite of coverage one doses MuCV to children. Compared with the period of the 1 dose MuCV immunization strategy, the incidence the groups coverage two doses MuCV was significantly reduced and lower the groups coverage one dose MuCV, but the prevalence and GMC were higher than that of the groups coverage one dose MuCV.

Objective: To investigate the effect of human umbilical cord mesenchymal stem cells (hUCMSCs) on the immune function and prognosis of patients with decompensated hepatitis B cirrhosis. Methods: A total of 65 patients with decompensated hepatitis B cirrhosis were divided into observation group and control group. The patients in the observation group were given intervention (via the proper hepatic artery or the portal vein) and intravenous infusion of 4×10 8 hUCMSCs in two doses, as well as the same basic treatment as in the control group. The patients in the control group were given conventional medical treatment. ELISA as used to measure the serum levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNFα), interleukin-10 (IL-10), and transforming growth factor-β (TGFβ) in the observation group before surgery and at 1 week after surgery, as well as the serum levels of IL-6, TNFα, IL-10, and TGFβ in the control group on admission and at 1 week after admission. Flow cytometry was used to measure the percentage of lymphocyte subsets in the observation group before surgery and at 1 week after surgery, as well as that in the control group on admission and at 1 week after admission. In addition, the patients' prognosis and major complications during hospitalization were observed in both groups, and the patients were followed up for 24 weeks to record the number of deaths. The t-test was used for comparison of continuous data, and the chi-square test was used for comparison of categorical data which were expressed as percentages. Results: At 1 week after the transplantation of hUCMSCs, compared with the control group, the observation group had significant reductions in the serum levels of IL-6 and TNFα and significant increases in the serum levels of IL-10 and TGFβ (all P < 0.001), as well as significant increases in the percentages of T4 cells and Treg cells and significant reductions in the percentages of T8 cells and B cells (all P < 0.05). There were no significant differences in the changes in T3 cells and natural killer cells between the two groups ( P > 0.05). Compared with the control group, the observation group had a significantly lower probability of progression to liver failure (6.45% vs 14.71%, P = 0.017). Conclusion: In the treatment of patients with decompensated hepatitis B cirrhosis, transplantation of UCMSCs can inhibit the proliferation of T cells and B cells and the differentiation of T8 cells, upregulate Treg cells, promote the secretion of immunosuppressive cytokines, and reduce the production of inflammatory cytokines. Therefore, it can alleviate liver inflammatory response and liver cell damage and reduce the probability of hepatic failure.

Hybrid halide perovskites represent one of the most promising solutions toward the fabrication of all solid nanostructured solar cells, with improved efficiency and long-term stability. This article aims at investigating the properties of CH3NH3PbI3 with controlled loading time in CH3NH3I solution via a two-step sequential deposition and correlating them with their photovoltaic performances. It is found that the optimum PCE of the loading time in the CH3NH3I solution is possible only at a relatively short time (10 min). Prolonging the loading time will degrade the perovskite film, and deteriorate the device performance by introducing a large amount of excessive defects and recombination. However, even if the material band gap remains substantially unchanged, a suitable loading time can dramatically improve the charge transport within the perovskite layer, exhibiting the out-standing performances of meso-superstructured solar cells.