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To address the timely acquisition of channel state information in reconfigurable intelligent surface (RIS)-assisted millimetre wave (mmWave) multiple-input multiple-output (MIMO) systems, a channel estimation scheme based on tensor decomposition was proposed. Firstly, a channel training mechanism with low pilot overhead was designed using a few passive reflection units and constructing a phase shift matrix. Then, a non-iterative channel estimation algorithm was derived using tensor canonical polyadic decomposition with Vandermonde structure constraints. Theoretical analysis indicated that the minimum pilot overhead of the proposed scheme only depended on the product of the subchannel path numbers of the reflection links and exhibited low computational complexity. Simulation results further verify the superiority of the proposed scheme compared to other methods.

Aluminum foam sandwich structure （aluminum foam sandwich, AFS） not only has the excellent characteristics of aluminum foam lightweight, damping and shock absorption, energy absorption and protection, but also can solve the problems of low strength and easy damage of single aluminum foam, so it has a broad application prospect in aerospace, automobile manufacturing, rail transportation, precision machine tools and other industrial fields. In this paper, based on the melt foaming method, an aluminum foam sandwich structure with the size of 80 mm×80 mm×18 mm was successfully prepared using pure TA2 as the panel and Al-2Ca alloy as the foaming base material, and a large number of uniform pores were observed in the foam core, of which the polyhedral pores occupied a large area. A binding interface with an average thickness of 7.5 μm was observed between the panel and the core layer，where the elements diffused at the binding layer and existed in the form of intermetallic compounds. The bending test results show that the load curves of sandwich structures with different densities show three distinct areas: linear elastic zone, rapid load drop zone and flatform zone. The maximum peak load and yield strength of the sandwich structure are 1120.5 N and 15.64 MPa respectively. The bending strength of AFS materials increases with the increase of density and the decrease of core porosity. When the bending degree is 15 mm and the AFS density increases by 15.9%, the bending energy absorption WEA and WSEA increase by 3.59 and 3.22 times respectively. In the process of bending test, the failure modes are composed of compressive compaction deformation of aluminum foam core layer, shear and cracking of core material, bending deformation and peeling failure of TA2 panel, and various failure modes of AFS material are formed under the joint action of different stresses at different positions of the sample.

Objective: To evaluate the intrauterine state of fetuses with pregnancy-induced hypertension (PIH) through quantitative measurement of placenta by three-dimensional power Doppler ultrasonography, and to judge the value of three-dimensional power Doppler in PIH fetuses., Methods: A total of 50 pregnant women with PIH in our hospital from November 2012 to August 2014 were enrolled into the observation group, while 50 cases were randomly selected into the control group to match the former group's gestational week (GA). The placental vascularization index (VI), flow index (FI) and vascularization flow index (VFI) were quantitatively measured by three-dimensional power Doppler ultrasonography in the two groups. SPSS 19 statistics software was used to do the linear regression for the above parameters.And those parameters of the two groups were compared by t test. P<0.05 was deemed significant., Results: The detection ratio of fetal placental VI, FI and VFI of the whole 100 cases was 100%. The regression equation of VI and GA was: Y=0.394X-5.358, R² = 0.694, P<0.05; the regression equation of FI and GA was: Y=0.801X+5.61, R² = 0.807, P<0.05; the regression equation of VFI and GA was: Y=0.225X-4.148, R² = 0.691, P<0.05. t tests showed the differences of the means of placental VI, FI and VFI between the observation group and the control group were statistically significant (all P<0.05)., Conclusions: VI, FI and VFI of placenta measured by three-dimensional power Doppler examination increase with the increase of GA, and the means of placental VI, FI and VFI in PIH patients are less than those in normal cases. Quantitative measurement of placenta with three-dimensional power Doppler ultrasound has its own advantages, and can evaluate the status of placenta of PIH fetus accurately.

Objective: To establish the research model of ovarian carcinoma in nude mice, and to explore the effect of Paris Phyllin VII combined with silica nano complex on the inhibition and the antioxidant ability of ovarian carcinoma in nude mice., Method: Nude mice models with ovarian carcinoma were established by axillary subcutaneous inoculation of human SKOV3/DDP resistant ovarian cancer cell 200 µl and were used in the experiment. Treating the nude mice with Paris Phyllin VII combined with silica nano complex by gavage for 15 days to observe the weight change of the nude mice, tumor inhibition effect and changes of serum antioxidant capacity., Results: Compared with the negative control group, tumor inhibition rate increased significantly in Paris Phyllin VII combined with silica nano complex treatment group, and was higher than that in both Paris Phyllin VII treatment only and silica nano composites treatment only group. The serum superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) level of Paris Phyllin VII combined with silica nano complex treatment group was significantly higher than that of control group, Paris Phyllin VII treatment only and silica nano composites treatment only group. The serum malonaldehyde (MDA) level of Paris Phyllin VII combined with silica nano complex treatment group was significantly lower than that of the negative control group., Conclusion: Paris Phyllin VII combined with silica nano complex treatment can inhibit the ovarian carcinoma in nude mice, which may mediate by the enhancement of antioxidant capability in nude mice with ovarian cancer.

Objective: To explore the drug resistance of Chonglou saponin VII plus silica nano complex for ovarian cancer., Methods: The method of thiazolyl blue tetrazolium blue (MTT) was employed for determining the proliferation inhibition rate of Chonglou saponin VII plus silica nano composite for SKOV3/DDP drug-resistant human ovarian cancer cell. Flow cytometry and Hoechst 33342 staining were used for detecting apoptosis rate and cell cycle phase distribution. And the changes of apoptosis-related protein were examined by immunoblot assay., Results: There were obvious inhibitory effects of Chonglou saponin VII on cell proliferation. The inhibition rate increased with rising drug concentration with an obvious dose-effect relationship (P < 0.05). At the same time, the cell proliferation inhibition rate significantly improved at 48 h versus 24 h (P < 0.05). Flow cytometry and Hoechst 33342 staining showed that, after a 24 h treatment of SKOV3/DDP cells with 50 and 100 µmol/L Chonglou saponin VII, early apoptotic cell ratio significantly increased compared with control group., Conclusion: The composite of Paris polyphylla saponin VII and silica nano has obvious proliferation inhibitory effects on SKOV3/DDP cells. And there is a significant concentration dependence and it also has some correlation with time. The above composite can increased the proportion of early apoptotic cell ratio.

Objective: To establish the reference values of thalamus, caudate nucleus and lenticular nucleus diameters through fetal thalamic transverse section., Methods: A total of 265 fetuses at our hospital were randomly selected from November 2012 to August 2014. And the transverse and length diameters of thalamus, caudate nucleus and lenticular nucleus were measured. SPSS 19.0 statistical software was used to calculate the regression curve of fetal diameter changes and gestational weeks of pregnancy. P < 0.05 was considered as having statistical significance., Results: The linear regression equation of fetal thalamic length diameter and gestational week was: Y = 0.051X+0.201, R = 0.876, linear regression equation of thalamic transverse diameter and fetal gestational week was: Y = 0.031X+0.229, R = 0.817, linear regression equation of fetal head of caudate nucleus length diameter and gestational age was: Y = 0.033X+0.101, R = 0.722, linear regression equation of fetal head of caudate nucleus transverse diameter and gestational week was: R = 0.025 - 0.046, R = 0.711, linear regression equation of fetal lentiform nucleus length diameter and gestational week was: Y = 0.046+0.229, R = 0.765, linear regression equation of fetal lentiform nucleus diameter and gestational week was: Y = 0.025 - 0.05, R = 0.772., Conclusions: Ultrasonic measurement of diameter of fetal thalamus caudate nucleus, and lenticular nucleus through thalamic transverse section is simple and convenient. And measurements increase with fetal gestational weeks and there is linear regression relationship between them.

Objective: To explore the value of prenatal ultrasound in assessing thyroid function in fetuses of hyperthyroidism pregnant women and establish the reference values of fetal thyroid transverse diameter and anteroposterior diameter for different gestational weeks., Methods: For observation group, 30 cases of pregnant women diagnosed as hyperthyroidism were recruited from our hospital from November 2012 to November 2013. And another 100 cases of pregnant women during 20 to 40 weeks of gestational weeks were selected into control group. The measured ultrasonic parameters included fetal biparietal diameter, head circumference, abdominal circumference, femur length, amniotic fluid index, heart rate, fetal thyroid transverse diameter, anteroposterior diameter and fetal movement frequency. A fetus was considered as suspected positive when they were less than gestational age, thyroid measurement higher than 95% confidence interval, heart rate over 160 beats/min or less than 120 beats/min. In the observation group, the blood levels of thyroid stimulating hormone and thyroxine were measured after birth., Results: The regression equation of fetal thymus transverse diameter and GA was: Y = 0.053X - 0.096, R² = 0.758, P < 0.05; the regression equation of fetal thymus anteroposterior diameter and GA: Y = 0.034X - 0.397, R² = 0.596, P < 0.05. The measured value of 95% confidence interval for 2 cases in observation group exceeded that in control group. There were fetal tachycardia (n = 2), bradycardia (n = 1), low TSH after birth (n = 2), T4 elevation after birth (n = 1) and clinical T4 high value (n = 1)., Conclusion: Ultrasonic assessment of fetal thyroid function is timely and noninvasive. And it has an irreplaceable value in hyperthyroidism pregnant women. And normal reference values of fetal thyroid measurements are established for 20-40 gestation weeks.

Objective: To measure the ultrasonic parameters of transverse diameter, anteroposterior diameter and volume of fetal thymus through two and three-dimensional (2D and 3D) probes, establish normal reference range of fetal thymus development and assess the correlation between fetal intrauterine growth restriction and fetal thymus development., Methods: A total of 53 patients with suspected fetal intrauterine growth restriction (IUGR) at our hospital from December 2012 to May 2014 were selected into the observation group while another 53 cases as the control group corresponding to the former group's gestational week (GA). The transverse and anteroposterior diameters were measured in the three vessel view by 2D-ultrasound and the volume of fetal thymus was measured through 3D ultrasound. The control parameters were analyzed by linear regression analysis. And two groups of parameters were tested by rank sum test. P < 0.05 was deemed significant., Results: The regression equation of fetal thymus transverse diameter and GA was: Y = 0.14X-1.174, R² = 0.766, P < 0.05; the regression equation of fetal thymus anteroposterior diameter and GA was: Y = 0.49X-0.166, R² = 0.792, P < 0.05; the regression equation of fetal thymus volume and GA was: Y = 0.652X-10.611, R² = 0.791, P < 0.05. Two groups underwent rank sum test of fetal thymus transverse diameter, anteroposterior diameter and volume (P < 0.05)., Conclusion: Fetal thymus transverse diameter, anteroposterior diameter and volume increase with gestational weeks. In IUGR, fetal thymus transverse diameter, anteroposterior diameter and volume are less than those of the same GA fetal thymus.