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Ba 0.5 Sr 0.5 TiO 3 (BST) nanoparticles were coated with SiO 2 using a chemical process. SiO 2 -coated BST was used as the starting material to prepare BST- x SiO 2 ( x  = 0, 1.0, 2.0, 3.0, 4.0, and 5.0 wt%) composites via a conventional ceramic process. The influence of SiO 2 on the structure and properties of these composites was systematically studied. Scanning electron microscopy (SEM) results showed that the porosity of the composites was obviously reduced by the addition of SiO 2 . X-ray diffraction (XRD) results indicated that, besides the perovskite phase of BST, a traceable secondary phase of BaTiSiO 5 also existed. The formation of BaTiSiO 5 was due to the reaction between SiO 2 and barium from BST. This resulted in a lower phase transition temperature of BST phase in the composites. It was found that the dielectric constant and loss decreased with increasing SiO 2 content. All the composites exhibited a low dielectric loss (< 0.01) and an almost frequency independent dielectric constant in a frequency range from 100 Hz to 100 kHz. All the composites exhibited a high tunability (> 47%). Although the tunability decreased with increasing SiO 2 content, a higher tunability was achieved in the composites because the composites exhibited a much higher breakdown strength than the pure BST ceramics. Additionally, it was found that the tunability of the composites increased with the decrease of the operating temperature. [ABSTRACT FROM AUTHOR]

Ba 0.5 Sr 0.5 TiO 3 (BST) nanoparticles coated with SiO 2 were used as the starting material to prepare BST- x SiO 2 ( x  = 0, 1.0, 2.0, 3.0, 4.0 and 5.0 wt%) ceramic-glass composites. The coated SiO 2 results in the sintered composites with a lower porosity. All the composites exhibited an almost frequency independent dielectric constant that corresponds with a quite low dielectric loss (tan δ  < 0.02) over a frequency range from 100 Hz to 1 MHz. It is found that the Curie temperature decreased with increasing x due to the reaction between the SiO 2 and BST. As the x increased, the dielectric constant of the composites decreased and the electric breakdown strength increased. Interestingly, it is also found that the charge-discharge efficiency increased with an increasing x . The energy-storage density of more than 2.5 J/cm 3 with a charge-discharge efficiency of about 80% was achieved in the composite with x  = 1.0 wt%. [ABSTRACT FROM AUTHOR]

This paper presents a piezoelectric-excited membrane device for rapid measurement of liquids viscosity and density. The working principle of the device is based on membrane’s resonant frequency and Q factor responses to the damping effects of a surrounding liquid. The dependences of the resonant frequency and Q factor on liquids viscosity and mass density were theoretically investigated using a sphere-end oscillator model in viscous liquids and compared to experimental results. The theory and experimental results show that the piezoelectric-excited membrane can be used to measure liquids viscosity in a range from 19.88 cP to 1733 cP and mass density in a range from 0.829 g/cm 3 to 0.886 g/cm 3 . Hence, the piezoelectric-excited membrane device is a promising candidate for rapid measurement of liquids viscosity and mass density, especially for wide-range viscosity measurement. [ABSTRACT FROM AUTHOR]

Abstract: Ceramic–polymer 0–3 nanocomposites, in which nanosized Ba0.5Sr0.5TiO3 (BST) powders were used as ceramic filler and P(VDF–CTFE) 88/12mol% [poly(vinylidene fluoride–chlorotrifluoroethylene)] copolymer was used as matrix, were studied over a concentration range from 0 to 50vol.% of BST powders. It is found that the solution cast composites are porous and a hot-press process can eliminate the porosity, which results in a dense composite film. Two different configurations used in the hot-press process are studied. Although there is no clear difference in the uniformity and microstructure of the composites prepared using these two configurations, the composites prepared using one figuration exhibit a higher dielectric constant with a lower loss. For the composite with 40vol.% BST, a dielectric constant of 70 with a loss of 0.07 at 1kHz is obtained at room temperature. The composites exhibit a lower dielectric loss than the polymer matrix at high frequency. However, at low frequency, the composites exhibit a higher loss than the polymer matrix due to a low frequency relaxation process that appears in the composites. It is believed that this relaxation process is related to the interfacial layer formed between BST particle and the polymer matrix. The temperature dependence of the dielectric property of the composites was studied. It is found that the dielectric constant of these composites is almost independent of the temperature over a temperature range from 20 to 120°C. [Copyright &y& Elsevier]

Two types of magnetostrictive resonators – magnetostrictive microcantilever (MSMC) and magnetostrictive particle (MSP) – have been introduced as sensor platforms. Their principles and advantages as sensor platforms are discussed along with the materials selection. A detailed and complete comparison between the MSMC and MSP is given. It is concluded that for the resonators with the same size, an MSP exhibits a higher sensitivity and has a much higher resonant frequency. For the resonators with the same resonant frequency, MSMCs exhibit a much higher sensitivity and have a much smaller size than MSPs. Using antibody as the sensing element, MSP biosensors for in situ detection of Escherichia coli and Listeria monocytogenes are developed and characterized. These biosensors exhibit a high performance. For example, the MSP-antibody biosensors of 1mm×0.3mm×15μm exhibit a detection limit less than 100cfu/ml for in situ detection of bacterial cell in water. A new type actuator is introduced using MSPs. The MSP actuator is operated using AC magnetic field with a frequency close to, but different than, its resonant frequency. The MSP actuator exhibits an unlimited displacement, and its moving direction is controlled by the operating frequency used. [ABSTRACT FROM AUTHOR]

Abstract: A new design as piezoelectric membrane is introduced to improve the performance of a diaphragm based biosensor platform. In the design, stress is introduced into the diaphragm by a vacuum chamber and makes it work as membrane with a higher sensitivity and a higher Q factor. The mass sensitivity of stress-improved membrane was investigated and an effective mass approach is used to simulate the sensitivity of the device for a point mass load. Piezoelectric membranes with different sizes have been built using PVDF piezo-polymers. These devices were characterized in air and in water. The experimental results are consistent with the theoretical simulation and indicate that the device in liquid can have a higher Q factor than that in air. A theoretical model, which is a sphere executing translatory oscillations in viscous fluid, was used to analyze the Q factor in liquid environment. The results indicated that the large Q factor in liquid can be attributed to the relative large effective mass of membrane in liquid environment. [Copyright &y& Elsevier]

Relaxor ferroelectrics are materials exhibiting dielectric dispersions in their maximum permittivity température without macroscopic phase transition into a ferroelectric state. Their exceptional properties are exploited in a variety of dielectric and piezoelectric applications. As it is generally believed that polar nanoregions play a crucial role in relaxor behavior, there are great interests in exploring how the atomic structures affect the relaxor properties. Here, using the dark field imaging and atomic-resolution electron microscopy, we investigate the nano and atomic structure of a lead-free ferroelectric-relaxor Ba(Ti1-xSnx)O3 system at high temperature. The local atom displacements and their spatial correlations are measured, and the atomic structure of static polar nanoregions in the relaxors is reported. For the materials exhibiting normal ferroelectricity, no such static polar structures can be seen. Based on our experimental observations, we suggest the static polar nanoregions are responsible for the relaxor behavior in this lead-free system. [ABSTRACT FROM AUTHOR]

Abstract: Magnetostrictive microcantilever (MSMC), as a high-performance biosensor platform, was introduced recently. By using physical absorption, an antibody against Escherichia coli is immobilized onto the surface of the MSMC to form a biosensor. The real-time and in situ detection of E. coli in water using the biosensor is reported. The responses of the biosensor in E. coli suspension with different concentrations were studied, which were used to determine the detection limit of the biosensor. It is confirmed by using SEM observation and a control sensor approach, respectively, that the experimentally observed response of the biosensor is due to the binding of E. coli on the surface of the biosensor. It is found that the detection limit is improved by reducing the size of the MSMC, which is consistent with the theoretical calculation. For an MSMC with the size of 1.5mm×0.8mm×35μm, the detection limit is 105 cfu/ml. [Copyright &y& Elsevier]

Abstract: Magnetostrictive micro/milli-cantilever (MSMC) was recently introduced as a promised biosensor platform due to its high performance in liquid and wireless nature. To better understand the resonance behavior of the MSMC, unimorph-type MSMCs with thickness about 30μm and different lengths and widths were fabricated, and their resonance behaviors were investigated in air and in different liquids. The influence of the driving magnetic fields and the surrounding media on their resonance behavior was also studied. It is found that the amplitude of the driving ac magnetic field has very weak influence on the resonance frequency. On the basis of the damping effect of different liquids on the resonance behavior of the MSMCs, it is found that the characteristic frequency of the MSMC is linearly dependent on the density of the liquid media, while the Q value is inversely proportional to the square root of the product of the density and viscosity of the liquid media. It is also found that the damping effect of liquid on the MSMC can be treated as a damping string of sphere and the effect radius of the oscillating sphere for an MSMC is a constant. The value of the effect radius for different MSMCs was experimentally determined. Additionally, the resonance frequency of the MSMC is very stable. Due to their wireless nature, MSMCs are suitable for the development of a cantilever array. It is experimentally demonstrated that the characterization of an MSMC array is as simple as a single MSMC. The detection of Bacillus anthracis spores in water was performed using MSMC biosensors in a real-time manner to demonstrate the in situ detection capability. [Copyright &y& Elsevier]

Abstract: Objective: This study sought to describe the surgical management of right portal venous (PV) branches encountered among 104 cases of right lobe living donor liver transplantation (LDLT). Methods: From January 2002 to September 2007, we performed 104 cases of right-lobe LDLT including 11-donors who had anomalous right portal venous branches (APVB). One recipient had PV sponginess hemangioma. The donor right PV branches were type I in 93 cases, type II (trifurcation) in nine cases, and type III in two cases. Except one narrow bridge of tissue excision, the PV branches were transected on the principal of donor priority: PV branches were excised approximately 2 to 3 mm from the confluence while leaving the donor''s main portal vein and confluence intact. In type II APVB, donor PV branches were obtained with two separate openings in six cases; with two separate openings joined as a common orifice at the back table in two cases, with one common opening with a narrow bridge of tissue in one case. In type III APVB, the donor right anterior and posterior PV branches were obtained with separate openings. The donor right PV branches with one common opening in 92 cases of type I PV branches and a joined common orifice in three cases of type II APVB were anastomosed to the recipient''s main portal vein or to right branching. As the unavailable recipient PV for sponginess hemangioma, one case of type I right PV branches was end-to-end anastomosed to one of the variceal lateral veins of about 1 cm diameter in a pediatric patient. The PV were reconstructed as double anastomoses in six type II APVB and in one type III APVB obtained with two separate PV openings. In the another type III APVB reconstruction, we successfully utilized a novel U-shaped vein graft interposition. Results: The type II APVB donor receiving a narrow bridge of portal vein tissue excision developed portal vein thrombosis on the third postoperative day and underwent reexploration for thrombectomy. There were no vascular complications, such as portal vein thrombosis or stricture among other donors or all recipients. The velocity of blood flow in the U-graft was normal. The anastomosis between the type I donor right portal vein and recipient variceal lateral vein was unobstructed. Conclusion: Right PV branches should be excised on the principal of donor priority while leaving the donor''s main portal vein and confluence intact. Single anastomoses was the fundamental procedure of right branch reconstruction. Double anastomoses could be used as the main management for type II and type III APVB reconstruction. U-graft interposition may be a potential procedure for type III APVB reconstruction. Single anastomoses between the donor right portal vein and the recipient variceal lateral vein may be performed when recipient portal vein is unavailable. These innovations for excision and reconstruction of right PV branches were feasible, safe, and had good outcomes. [Copyright &y& Elsevier]

Crystallization behaviors and related dielectric properties of semicrystalline matrix in polymer-ceramic nanocomposites have been systemically investigated by using P(VDF-TrFE) 70/30 mol.% as matrix and Ba 0.5 Sr 0.5 TiO 3 nanoparticles as filler. It is found that due to the presence of ceramic nanofiller, there are two types of crystals formed in the matrix: one formed on the surface of the ceramic nanoparticles and the other formed in the polymer. The former favors the all-trans β phase due to the interaction between matrix chains and ceramic surface. The later has defects that result in two low-temperature phases: the well-ordered β phase and less-ordered β phase (i.e. β′ phase). The conformation defects of the β′ phase result in it a lower dielectric permittivity than β phase. The proportion of β' phase decreases with increasing ceramic content and only β phase can be observed in the nanocomposites with a ceramic content higher than 35 vol%. These results were reflected in and confirmed by the DSC analyses and the dielectric properties. [ABSTRACT FROM AUTHOR]

Aims: The objective of our study was to establish and verify a novel combined model based on multiparameter magnetic resonance imaging (MRI) radiomics and clinical features to distinguish intraspinal schwannomas from meningiomas., Materials and Methods: This research analyzed the preoperative magnetic resonance (MR) images and clinical characteristics of 209 patients with intraspinal tumors who received tumor resection at three institutions. 159 individuals from institutions 1 and 2 were randomly assigned into a training group (n=111) and a test group (n=48) in a 7-3 ratio. A nomogram was constructed using the training cohort and was internally and externally verified in the test cohort and an independent validation cohort (n=50). Model performance was assessed utilizing the area under the curve (AUC) of receiver operating characteristics (ROC), decision curve analysis (DCA), and calibration curves., Results: The nomogram exhibited superior predictive efficacy in distinguishing between spinal schwannomas and meningiomas when compared to both the radiomics model and the clinical model. The nomogram yielded AUCs of 0.994, 0.962, and 0.949 in the training, test, and external validation cohorts, respectively, indicating its exceptional differentiating ability. The DCAs demonstrated that the nomogram yielded the best net benefit. The calibration curves indicated that the nomogram got good agreement between the predicted and the actual observation., Conclusion: This research suggests that the nomogram incorporating clinical and radiomic features may be an effective auxiliary tool for distinguishing between intraspinal schwannomas and meningiomas, and has important clinical significance for clinical decision-making and prognosis prediction., (Copyright © 2024 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Objective: To discuss the clinical value of preserving subvalvular structure in mitral and aortic valve replacement surgery and its effect on left ventricular contractility. Methods: A total of 97 patients who underwent mitral valve replacement surgery in the Adult Cardiac Surgery of Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital from June 2016 to December 2018 were selected as the research subjects, of whom 45 cases were preserved subvalvular structure and 52 cases were in the total resection group (intraoperative total resection of the mitral valve and subvalvular chordae tendineae). General cardiac function indexes and left ventricular function quantitative indexes were compared before and in 3 months and 6 months after the operation of the two groups; The changes of the overall longitudinal strain of the long axis of the apex and the overall circumferential strain of the short axis of the left ventricle determined by the two-dimensional speckle tracking technology were compared before and after the operation. Results: The ages of the patients in the preservation group and the total resection group were (41.8±11.3) and (43.3±10.6) years old, respectively, and the male proportions were 58.0% (26 cases) and 44.0% (23 cases), respectively, with no significant difference (all P >0.05). The aortic occlusion time and cardiopulmonary bypass time of the patients in the preservation group were (57.8±4.5) and (78.6±6.7) min, respectively, which were longer than those in the total resection group [(48.1±4.4) and (48.1±4.4) min, respectively] (all P <0.05). The left atrial pressure of the patients in the preservation group at shutdown was (8.4±1.8) mmHg (1 mmHg=0.133 kPa), which was lower than that of the total resection group (11.3±2.5) mmHg ( P <0.001). There were interaction effects between groups and time in regards to the left ventricular end-diastolic diameter ( LVEDD ), left ventricular ejection fraction ( LVEF ) and Tei index, as well as the strain rate of mitral annulus and left ventricular wall of interventricular septum of the preservation group and the total resection group (all P <0.05). LVEDD and LVEF of patients in the preservation group at 3rd month after operation were (44.7±4.0) mm and (45.5±4.2) mm, and at 6th months were (56.5±4.9)% and (58.8±5.0)%, respectively, all larger than (42.7±3.6) mm and (42.7±3.6) mm, (54.5±4.6)% and (56.3±4.8)% of the total resection group. The measured value of LVESD in the preservation group at 3rd month after surgery was (32.6±3.2) mm, which was greater than that in the total resection group (31.2±3.4) mm ( P <0.05). The Tei index of patients in the preservation group at 3rd and 6th months after surgery were 1.0±0.2 and 0.8±0.2, respectively, which were lower than those in the total resection group 1.2±0.3 and 0.9±0.2 (all P <0.05). Conclusion: Preserving the subvalvular structure during mitral valve replacement surgery can better improve the patient's left ventricular function and left ventricular systolic capacity.

Objective: To retrospectively analyze the occurrence and treatment of perioperative complete atrioventricular block (CAVB) by transcatheter aortic valve implantation (TAVI). Methods: A total of 65 patients who underwent TAVI via femoral artery in the Heart Center of Henan People's Hospital from October 2017 to May 2021 were enrolled. Perioperative data of patients were recorded. The patients were divided into two groups according to whether complete atrioventricular block was occurred during TAVI: complete atrioventricular block group (Group CAVB) and non-complete atrioventricular block group (Group NCAVB). Multivariate logistic regression model was used to analyze the risk factors of complete atrioventricular block during transcatheter aortic valve implantation. The incidence of perioperative complications were recorded. Results: The patients age was (69.1±7.3) years old. and there were 35 males and 30 femals. There were 15 patients in group CAVB with complete atrioventricular block and 50 patients in group NCAVB. Multivariate analysis showed that preoperative right bundle branch block [ OR (95% CI ) vs 3.325 (2.132-13.061), P =0.005] and severe aortic valve calcification [ OR (95% CI ) vs 1.271 (1.052-3.326), P =0.030] were independent correlative factors for CAVB during TAVI perioperative period. The implantation rate of permanent pacemaker in group CAVB was 73.3% (11 cases), which was higher than 6.0% (3 cases) in group NCAVB ( P <0.001). Conclusions: It indicated that preoperative right bundle branch block and severe aortic valve calcification are correlative factors for complete atrioventricular block for TAVI. The implantation rate of permanent pacemaker in complete atrioventricular block group increased significantly.

A sensitivity- and resolution-improving method for a low-frequency micro-vibration accelerometer is presented in this paper. A sensitivity model of the measurement system is derived and established. The key parameters that limit the sensitivity and the resolution of the accelerometer were identified through the sensitivity coefficient analysis method. The structural parameters and the signal process method were then optimized. Experimental results show that the sensitivity of the accelerometer has improved from 1.10 V/(m/s 2 ) to 19.21 V/(m/s 2 ), and the resolution has improved from 1.47 mm/s 2 to 0.21 mm/s 2 . The lowest working frequency range has expanded from 1 Hz to 0.7 Hz. The presented method is effective and cheap and can be applied to other sensors.

Objective: The operative approach and steps of laparoscopic right hemicolon cancer radical resection have been standardlized and professional consensus has been reached. However, some detailed issues such as the handling of Henle's trunk and whether to preserve the right gastroepiploic vein (RGEV) still remain controversial. This study investigates the safety, feasibility, short- and long-term outcomes of preserving RGEV during laparoscopic right hemicolectomy. Methods: A retrospective cohort study was carried out. Clinical data of 92 patients undergoing laparoscopic right hemicolectomy in Taizhou People's Hospital from March 2016 to May 2018 were retrospectively analyzed. All the patients were treated with complete mesocolon resection (CME) and had complete postoperative pathological data and follow-up data. Based on the tumor location, 49 patients preserved RGEV (preservation group) and 43 did not (non-preservation group). Pathological data, postoperative complications, short- and long-term outcomes were compared between the two groups. Results: There were no significant differences in baseline data between the two groups (all P >0.05). No significant differences were found in operation time, intraoperative blood loss, unplanned reoperation, anastomotic leak, number of harvested lymph nodes, number of metastatic lymph node, and time to food intake after surgery between two groups (all P >0.05). Compared with non-preservation group, the preservation group had faster recovery of anal gas passage after operation [(3.1±1.0) days vs. (4.0±1.7) days, t =-2.787, P =0.007], shorter length of hospitalization [(11.5±1.5) days vs. (15.0±7.9) days, t =-2.823, P =0.007], and reduced the hospitalization expenses [(46 000±5000) yuan to (57 000±33 000) yuan, t =-2.076, P =0.044]. No postoperative gastroparesis (PGS) occurred in the preservation group, while 6 cases in the non-preservation group developed gastroparesis during perioperative period ( P <0.05). The median time of follow-up time was 31.8 (5.2-43.7) months. The overall survival time of the preservation group and non-preservation group was (35.4±1.8) months and (37.6±1.7) months, respectively without significant difference ( P =0.336); the disease-free survival was (32.0±2.2) months and (35.5±2.0) months, respectively without significant difference as well ( P =0.201). Conclusions: Dissection of the Henle's truck and preservation of RGEV is safe and feasible during laparoscopic right hemicolectomy, which can significantly reduce the incidence of postoperative gastroparesis, shorten the recovery time of postoperative intestinal function and hospitalization, and decrease the cost of hospitalization. The efficacy of RGEV preservation is similar to non-preservation of RGEV.

Objective: Breast cancer (BC) is the second most frequent malignancy worldwide. Hsa&#95;circ&#95;0008039 exerts the carcinogenic factors in BC. However, the pathogenesis of hsa&#95;circ&#95;0008039 involved in BC is still unclear., Patients and Methods: The expression levels of hsa&#95;circ&#95;0008039, microRNA-515-5p (miR-515-5p) and chromobox homolog 4 (CBX4) in BC tissues and cells were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Cell proliferation, migration and invasion were assessed by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) and transwell assays, severally. The binding relationship among hsa&#95;circ&#95;0008039, miR-515-5p and CBX4 was predicted by starBase, then verified by the dual-luciferase reporter assay and immunoprecipitation (RIP) assay. The interaction between hsa&#95;circ&#95;0008039 and miR-515-5p was confirmed by RNA pull-down assay. The protein level of CBX4 was detected by Western blot assay. The biological role of hsa&#95;circ&#95;0008039 was detected by xenograft tumor model in vivo., Results: Hsa&#95;circ&#95;0008039 was upregulated in BC tissues and cells, and expedited proliferation, migration and invasion of BC cells. MiR-515-5p was downregulated in BC tissues and cells and worked as a target of hsa&#95;circ&#95;0008039. CBX4 was highly expressed in BC tissues and cells, and contributed to proliferation, migration and invasion of BC cells. Hsa&#95;circ&#95;0008039 enhanced CBX4 expression by competitively binding to miR-515-5p, thereby promoting BC development. Hsa&#95;circ&#95;0008039 knockdown repressed BC tumor growth in vivo., Conclusions: These findings implicated that hsa&#95;circ&#95;0008039 contributed to proliferation, migration and invasion in vitro and promoted tumor growth in vivo by miR-515-5p/CBX4 axis in BC, suggesting a potential therapeutic strategy for BC treatment.

Objective: To investigate the predictive value of cervical length (CL) measured by transvaginal ultrasound for preterm birth <32 weeks, <34 weeks in twin pregnancies in the second and the third trimester of pregnancy. Methods: A total of 490 twin pregnant women with CL measured by transvaginal ultrasound during the second trimester of pregnancy (20-24 weeks) and the third trimester of pregnancy (28-32 weeks) delivered in Peking University Third Hospital, and Tongzhou Maternal and Child Health Hospital from January 2014 to December 2017 were collected, and 161 cases out of which were measured by CL during both the second trimester and the third trimester of pregnancy. Based on the measured gestational weeks, 427 cases were in the second trimester group and 224 cases in the third trimester group. The predictive value of CL for preterm birth was evaluated by calculating the optimal cut-off point with sensitivity and specificity. Logistic regression analysis was used to assess the relationship between CL and preterm birth after adjusting for confounding factors (age of pregnant women, chorionic status, mulipara, assisted reproductive pregnancy and pre-pregnancy body mass index). Results: (1) The median CL of pregnant women in the second trimester group and the third trimester group were 36 mm (33-40 mm) and 28 mm (18-33 mm) respectively. In the second trimester group, 151 cases (35.4%, 151/427) were preterm birth and 276 cases (64.6%, 276/427) were full-term birth; the median CL of preterm and full-term pregnant women were 34 mm (30-37 mm) and 37 mm (34-40 mm), respectively, with significant difference ( P <0.01). In the third trimester group, 100 cases (44.6%, 100/224) were preterm birth and 124 cases (55.4%, 124/224) were full-term birth; the median CL of preterm and full-term pregnant women were 22 mm (15-30 mm) and 31 mm (23-34 mm), respectively, with significant difference ( P <0.01). (2) Prediction of preterm birth <32 weeks and <34 weeks was performed with CL in the second trimester group. The area under the receiver-operating characteristics curve were 0.78 (95% CI : 0.70-0.86) and 0.71 (95% CI : 0.64-0.79), respectively. The optimal cut-off points were 36.5 mm and 33.5 mm, respectively. After adjusting for confounding factors, CL was inversely associated with preterm birth <32 weeks and <34 weeks of gestation. (3) Prediction of preterm birth <32 weeks and <34 weeks were performed with CL in the third trimester group. The area under the receiver-operating characteristics curve were 0.86 (0.75-0.96) and 0.75 (0.67-0.84), respectively. The optimal cut-off points were 17.5 mm and 18.5 mm, respectively. After adjusting for confounding factors, CL was inversely associated with preterm birth at <32 weeks and <34 weeks of gestation. Conclusions: CL measured by transvaginal ultrasound in the second and the third trimester is a good predictor for preterm birth of twin pregnancy. CL≤36.5 mm and ≤33.5 mm at 20-24 weeks of gestation could predict preterm birth <32 weeks and <34 weeks respectively. CL≤17.5 mm and ≤18.5 mm at 28-32 weeks of gestation could predict preterm birth <32 weeks and <34 weeks respectively.

Objective: In this study, we aimed to investigate the expression profile of C2H2 zinc finger (ZNF) 860 (ZNF860) in gastric cancer (GC), its prognostic significance and its potential regulatory network in GC., Patients and Methods: The level-3 data in the Cancer Genome Atlas-Stomach Adenocarcinoma (TCGA-STAD) was acquired for a secondary analysis, in which clinicopathological, genetic and survival data from 415 GC patients were collected., Results: The gastric cancerous tissues had significantly upregulated ZNF860 expression. In univariate analysis, male patients, no responses to primary therapy, with male patients and high ZNF860 RNA expression were associated with unfavorable RFS in early GC (stage I/II). Multivariate analysis showed that high ZNF860 RNA expression was independently associated with shorter recurrence-free survival (RFS) in patients with early GC (HR: 5.289, 95%CI: 1.839-15.214, p=0.002). Among 413 cases of GC tumors with copy number alteration (CNA) data available, 35 cases (8.5%) had DNA amplification (+1/+2), while 121 cases (29.3%) had DNA copy loss. ZNF860 amplification was associated with significantly elevated ZNF860 expression. In comparison, DNA copy loss did not necessarily result in ZNF860 downregulation. The methylation of 5 CpG sites in ZNF860 gene (cg24264962, cg24391989, cg10702818, cg15840985, and cg25692785) was negatively correlated with ZNF860 expression. Six genes (OSBPL10, FAM208A, TOPBP1, SPTY2D1, NAB1, and CMTM6) were positively co-expressed with ZNF860, suggesting that ZNF860 probably acts as a transcription enhancer in GC., Conclusions: ZNF860 RNA upregulation was an independent prognostic indicator in terms of RFS in stage I/II GC. DNA CNAs and methylation alterations might collaboratively regulate ZNF860 expression.

Objective: The aim of the study was to explore the pharmacological role of ulinastatin in rats with myocardium infarction (MI) and its underlying mechanism., Materials and Methods: Rats were randomly assigned into sham group, MI group, and ulinastatin group, with 8 rats in each group. MI model in rats was constructed and specific drug administrations were performed in each group. Electrocardiogram and hemodynamics were detected before and after animal procedures. Myocardium function in rats was accessed by determining serum levels of creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH). Hematoxylin and eosin (HE) staining was performed to detect the infarct area in rat myocardium. Terminal Deoxynucleotidyl Transferase dUTP Nick-end Labeling (TUNEL) assay was conducted to calculate the ratio of apoptotic cells in rat myocardium. Subsequently, relative oxidative stress indicators in rats were accessed, including total antioxidant capacity (T-AOC), catalase (CAT), glutathione (GSH), Superoxide Dismutase (SOD), malondialdehyde (MDA), and reactive oxygen species (ROS). Western blot was conducted to detect protein levels of nuclear factor E2-related factor 2 (Nrf2), Nuclear Factor κB (NF-Κb), heme oxygenase-1 (HO-1), and NAD(P)H:quinone oxidoreductase 1 (NQO1) in rat myocardium., Results: No significant differences in heart rate, the voltage of the QRS wave and Q-T interval were observed among rats in sham group, MI group, and ulinastatin group prior to the animal procedures. However, at the end of the animal procedures, rats in ulinastatin group showed higher heart rate and voltage of QRS wave, as well as shorter Q-T interval than those in MI group. Rats in ulinastatin group presented lower serum levels of CK-MB and LDH compared with those in MI group, whereas they did not return to baseline. Rats in ulinastatin group showed higher levels of LVSP, dP/dtmax, LVEDP, and -dP/dtmax than those in MI group. Larger infarct area was observed in MI group compared with that of sham group, whereas ulinastatin treatment remarkably reduced the infarct area. HE staining showed remarkable pathological lesions in MI rats, whereas ulinastatin group showed milder lesions in rat myocardium. TUNEL assay showed fewer TUNEL-positive cells in ulinastatin group than those of MI group. Levels of T-AOC, CAT, GSH, and SOD were remarkably higher in myocardium homogenate of MI group than sham group, whereas ulinastatin treatment significantly decreased these levels. Ulinastatin group showed less ROS accumulation and decreased MDA level in rats than those of MI group. Ulinastatin treatment upregulated Nrf2, HO-1, and NQO1, whereas downregulated NF-κB expression., Conclusions: Ulinastatin protects MI rats by inhibiting inflammatory response through activating Nrf2/NOS pathway.

Objective: To explore the effect of miR-19b on the function of P19CL6 cells and its molecular mechanism. Methods: Overexpression of miR-19b was carried out by transfecting miR-19b plasmid into the P19CL6 cells. MTT assay and flow cytometry were used to determine cell growth and apoptosis, respectively. Western blot was used to detect the expression level of Sox6 in P19CL6 cells. ELISA assay was used to detect the expression levels of apoptosis-related genes (Bax, Bcl-2) in P19CL6 cells at late-stage cardiac differentiation. Further online software TargetScan was used to predict the target genes of miR-19b and verified by dual luciferase reporter assay. Results: Our data showed that overexpression of miR-19b in P19CL6 cells significantly increased the cell growth rates and the apoptosis inhibition rates. The ratio of apoptosis-related proteins (Bax/Bcl-2) was significantly reduced. Results from the TargetScan and dual luciferase reporter showed that Sox6 is the direct target of miR-19b. Conclusions: We conclude that miR-19b might promote cell proliferation and inhibits cell apoptosis during the late-stage of cardiac differentiation by targeting Sox6 expression.

Objective: To investigate the regulation of JAK2 tyrosine kinase inhibitor ruxolitinib on extracellular matrix metalloproteinase (MMP in JAK2V617F positive myeloproliferative neoplasms (MPN) cells. Methods: ①Forty cases of newly diagnosed JAK2V617F positive MPN patients and 15 healthy volunteers as control in Baoding No.1 Hospital between January 2012 and December 2015 were enrolled in this study. JAK2V617F/JAK2 ratio was detected by real-time-PCR; the expression levels of phosphorylation protein tyrosine kinase 2 (p-JAK2) , MMP-2 and MMP-9 in pathological tissues of bone marrow were detected by immunohistochemistry. The bone marrow cells of JAK2V617F positive MPN patients were treated with ruxolitinib, then the migration ability and MMP-2, MMP-9 gene and protein expression levels were detected. ②The human erythroleukemia cell line HEL cells were treated with different concentrations of ruxolitinib (0, 50, 100, 250, 500, 1 000 nmol/L) . The cell viability was detected by CCK-8 test; cell migration ability was tested by transwell chambers. The mRNA expression levels of JAK2, MMP-2 and MMP-9 were detected by real-time-PCR. The protein expression levels of p-JAK2, MMP-2 and MMP-9 were detected by Western blot. Results: ①The expression levels of p-JAK2, MMP-2 and MMP-9 in the newly diagnosed group were significantly higher than control group respectively [ (78.56±24.55) % vs (41.59±17.29) %, P <0.05; (48.25±18.74) % vs (22.79±13.89) %, P <0.05; (53.29±19.28) % vs (15.56±14.96) %, P <0.05]. Spearman correlation analysis showed the positive correlation of MMP-2 and MMP-9 protein expression levels with JAK2V617F mutation ( r =0.526, P =0.001; r =0.543, P =0.001) . ② The proliferation of HEL cells was inhibited by different concentrations of ruxolitinib in time and dose dependent manner. ③Cell migration test showed the number of cells leaked to the low chamber in MPN patients bone marrow cells and HEL cells treated with 5 nmol/L of ruxolitinib group were significantly lower than that without ruxolitinib treatment after 24 h [ (154.7±27.5) vs (320.3±67.3) , t =13.47, P <0.05; (70.7±10.5) vs (135.3±16.7) , t =13.89, P <0.05]. The mRNA and protein expression levels of JAK2, MMP-2 and MMP-9 decreased with the increased concentration of ruxolitinib. Conclusion: Ruxolitinib inhibits MPN cell migration and expression of MMP-2 and MMP-9 via JAK2 signal pathway.

Objective: To explore the application of new chest holder in the median sternotomy for open heart surgery in adults. Methods: Two hundred adult patients in Henan Provincial People's Hospital from May 2013 to May 2015 were enrolled in the study and randomly divided into two groups. Experimental group included 100 cases who accepted the new type of chest holder in the open heart surgery. Control group were also composed of 100 cases whose sternums were fixed with the pure steel wire cerclage. Sternal closure time was recorded since the sternum closing. All subjects were followed up to obtain the chest incision healing, the incidence of sternal dehiscence, infection and secondary thoracotomy, and thus to estimated the effect of new chest holder. Results: All patients in the experimental group reached the effect of firm closed chest surgery. Sternal closure time of experimental group was much shorter than that of control group[(10±2) vs (21±4) min, P <0.001]. No sternal instability, dehiscence, infection and secondary thoracotomy were found during the follow-up. However, in the control group, 3 secondary thoracotomy cases, 6 sternal dehiscence cases and 2 sternal infection cases were detected. Conclusions: New type of chest holder in the median sternotomy for open heart surgery is more convenient with small surgical trauma. It can also effectively reduce the incidence of sternal instability, dehiscence, infection and secondary thoracotomy.

Objective: To evaluate the feasibility of retrograde transcatheter closure of ventricular septal defects (VSD) under trans-esophageal echocardiography (TEE)., Methods: Twelve patients with VSD, with 4 residual shunt, treated by transcatheter VSD closure under solely guidance of TEE were summarized. Mean age, body weight and average diameter of VSD in 12 cases were (11.58±6.57) years, (31.85±13.28) kg, (5.50±2.20) mm, respectively. All patients were treated by retrograde transcatheter closure under solely guidance of TEE. The post-operative efficiency was estimated by TEE immediately. Patients were followed up by echocardiography, X-ray examination and electrocardiogram at 24 hours, 1, 3 and 6 months after the procedures., Results: All 12 patients were treated successfully under solely guidance of TEE. The diameter of devices were 5-14 mm. There were 1 case with trivial residual shunt after the procedures immediately. No patients suffered from residual shunt, occluder malposition, peripheral vascular injury and pericardial effusion during the follow-up., Conclusion: Percutaneous transcatheter closure of VSD completely guided by TEE is safe and effective. This method could avoid the radiation and contrast media reaction, and also could simplify the procedure.

Understanding the magnetic structure of materials on a nanometre scale provides fundamental information in the development of novel applications. Here we show a site-specific electron energy-loss magnetic chiral dichroism method, first experimentally demonstrating that the use of transmitted electrons allows us to quantitatively determine atomic site-specific magnetic structure information on a nanometre scale. From one NiFe(2)O(4) nanograin in composite films, we extract its atomic site-specific magnetic circular dichroism spectra and achieve the quantitative magnetic structure information, such as site-specific total magnetic moments and orbital to spin magnetic moment ratios, by constructively selecting the specific dynamical diffraction conditions in electron energy-loss magnetic chiral dichroism experiments. The site-specific electron energy-loss magnetic chiral dichroism method shows its unique ability for solving the site-specific magnetic structure at nanoscale resolution, compared with X-ray magnetic circular dichroism and neutron diffraction. This work opens a door to meet the challenge of exploring the magnetic structures of magnetic materials at the nanoscale using transmitted electrons.

A series of oxygen deficient LuFe(2)O(4-δ) materials have been prepared under a controlled oxygen partial-pressure atmosphere. Measurements of magnetization reveal that the increase of oxygen deficiencies could evidently depress the ferrimagnetic phase transition temperature (T(N)). In additional to the well-known charge ordering within the (11(-)0) crystal plane, a visible structural modulation with q = (0,1/4.2,7/8) commonly appears on the (100) plane in the oxygen deficient samples. An aberration-corrected transmission electron microscopy study on the oxygen deficient samples demonstrates the presence of oxygen vacancies and local structural distortion. The atomic structural features in correlation with the structural modulation, distortion of the FeO(5) polyhedron and the (001) twinning domains have been also examined.

This article presents an investigation of the effect of salt and phage concentrations on the binding affinity of magnetoelastic (ME) biosensors. The sensors were fabricated by immobilizing filamentous phage on the ME platform surface for the detection of Bacillus anthracis spores. In response to the binding of spores to the phage on the ME biosensor, a corresponding decrease occurs in resonance frequency. Transmission electron microscopy (TEM) was used to verify the structure of phage under different combinations of salt/phage concentration. The chemistry of the phage solution alters phage bundling characteristics and, hence, influences both the sensitivity and detection limit of the ME biosensors. The frequency responses of the sensors were measured to determine the effects of salt concentration on the sensors' performance. Scanning electron microscopy (SEM) was used to confirm and quantify the binding of spores to the sensor surface. This showed that 420 mM salt at a phage concentration of 1 x 10(11) vir/mL results in an optimal distribution of immobilized phages on the sensor surface, consequently promoting better binding of spores to the biosensor's surface. Additionally, the sensors immobilized with phage under this condition were exposed to B. anthracis spores in different concentrations ranging from 5 x 10(1) to 5 x 10(8) cfu/mL in a flowing system. The results showed that the sensitivity of this ME biosensor was 202 Hz/decade.

A high performance capillary electrophoresis method has been developed for separation and quantitative analysis of glibenclamide in Xiaotangling tablets. Electrophoretic conditions were as follows: micellar electrokinetic capillary chromatography (MECC) mode, trimethoprimum as internal standard, uncoated fused silica capillary (34.8 cm/39.5 cm(effective/total length), 50 microns i.d.), 25 mmol/L borax-30 mmol/L SDS(pH 9.0), applied voltage 17 kV, (+)-->(-), temperature 28 degrees C, detection wavelength 228 nm, pressure injection 68.95 kPa.s. Glibenclamide was separated successfully from other components within 14 minutes under the optimum conditions, and the relative peak area of glibenclamide increased linearly with the increase of its concentration within the range of 25 mg/L-275 mg/L. The recovery was (100.6 +/- 1.4)%. The method is simple, rapid and well reproducible, and can be used as a reliable tool for the quality control of Chinese traditional medicine containing glibenclamide.

Qingkailing Oral Tonic and Shuanghuanglian Oral Tonic are two kinds of complex formlae of Chinese traditional patent medicine, and both contain Scutellaria baicalensis Georgi. Baicalin is referred to the main active component with functions of dispelling wind-heat to reduce fever and detoxicating, and takes effect on uppering respiratory tract infection and tonsillities. In this work a high performance capillary electrophoresis (HPCE) method was established for separation and quantitative analysis of baicalin in prescriptions containing Scutellaria baicalensis Georgi, based on the mode of capillary zone electrophoresis. Electrophoretic conditions are as follows: uncoated fused silica capillary (34.8/39.5 cm x 50 microns i.d.), 40 mmol/L borax buffer(pH 9.0), applied voltage 17 kV, polarity anode (inlet) to cathode (outlet), temperature 25 degrees C, detection wavelength 285 nm, injection 68.95 kPa x s. Under the optimum conditions, baicalin was separated successfully from other components within 15 minutes. The relative peak area of baicalin increased linearly with the increase of its concentration in the range of 10-640 mg/L. The recoveries were (100.31 +/- 1.98)% for Qingkailing Oral Tonic and (100.60 +/- 2.36)% for Shuanghuanglian Oral Tonic. The analytical results demonstrate the method is simple, rapid and well reproducible, and can be used as a reliable tool for the quality control of Chinese traditional medicines containing Scutellaria baicalensis Georgi.

High energy electron irradiation with a broad range dosage was carried out on poly(vinylidene fluoride trifluorethylene) copolymer 65/35 mol% and 50/50 mol% films at different temperatures from room temperature to a temperature close to the melt temperature. The effect of irradiation on the properties of the films, such as electric field-induced strain, dielectric and polarisation behaviors, and mechanical modulus, is presented. The irradiated films can exhibit a very large electric field-induced strain, more than 4.5% longitudinal strain, and 3% transverse strain. The transverse strain of the stretched film can compare with the longitudinal strain; that of the unstretched film is much smaller than the longitudinal strain. With regard to the dielectric and polarization behaviors, we found that irradiation changes the copolymer from a typical ferroelectric to a relaxor ferroelectric in which the behavior of microregions under the electric field plays the key role. Between the two copolymers studied, we found that the 65/35 copolymer is preferred for both longitudinal and transverse strain generation. A model is proposed to explain the experimental results that the amplitude of the charge electrostrictive coefficient (Q) increases with decreasing crystallinity.

Yinhuang Granule is a kind of complex formulae made up of extract of Flos lonicerae and that of Radix scutellariae, of the fuctions of dispelling wind-heat to reduce fever, detoxicating, relieving inflammation, promoting urination and tranquilizimg the mind and can be applied to upper respiratory tract infection and tonsillitis. Baicalin and chlorogenic acid are referred to main effective components of it. In this paper, the separation and determination of baicalin and chlorogenic acid in Yinhuang Granule by capillary electrophoresis is described. The experimental conditions are stated as follow: separation column: bare fused-sillica capillary (50 microns i.d., 370 microns o.d., total length 47 cm, 40 cm from the inlet to UV detector); electrolyte: 25 mmol/L borax, pH 8.5; detection wavelength: 310 nm; sampling: 17 kPa.s; running voltage: 25 kV, polarity from anode (inlet) to cathode (outlelt); temperature: 25 degrees C; internal standard: p-nitrobenzoic acid. The linear ranges of determination for baicalin and chlorogenic acid were 160-960 mg/L(r = 0.9993, RSD = 1.76%-2.33%) and 80-960 mg/L(r = 0.9989, RSD = 1.07%-2.51%), respectively. The recoveries of baicalin and chlorogenic acid were (102.09 + 1.74)% (RSD = 1.71%, n = 6) and (99.81 + 3.11)% (RSD = 3.12%, n = 6). The method is simple, fast and accurate. It can be used for the quality control of Yinhuang Granule and its related Chinese medicines.

A baseband integrated acoustooptic (AO) frequency shifter/modulator module that consists of a pair of titanium-indiffused proton-exchanged (TIPE) waveguide lenses and a pair of cascaded guided-wave AO Bragg cells has been realized in a Y-cut LiNbO(3) waveguide substrate 0.1 cmx1.0 cmx2.0 cm in size. A device module operating at the optical wavelength of 1.3 mum has provided a -3-dB tunable bandwidth of 120 MHz at baseband. The frequency-shifted or -modulated light propagates in a fixed direction, irrespective of the magnitude of frequency shift or modulation, and is focused into a spot (FWHM) of 6.2-mum size on the output edge of the waveguide. Accordingly, this optical frequency shifter/module can be directly interfaced with single-mode optical fibers to facilitate applications in fiber optic systems.

By utilizing murine tumor models bearing Ehrlich ascites carcinoma (EAC) and ascitic Sarcoma-180 (S-180), we investigated the in vivo antitumor effects of QEQ or/and the chemotherapeutic agent cyclophosphamide (CY) and their influence on the splenic natural killer (NK) activity, macrophage-mediated tumor cytolysis (MTC) activity and interleukin-2 (IL-2) production level of different groups of TBM. The results demonstrate that Qigong-emitted external Qi (QEQ) has inhibitory effects on tumor growth of tumor-bearing mice (TBM) and enhancing effects on antitumor immunologic functions of the tumor host simultaneously. Moreover, when used in combination with CY, QEQ can not only significantly increase the antitumor efficacy, but also markedly improve the compromised antitumor immunologic functions of the tumor host. Therefore, our findings suggest that in clinical practice of cancer treatment Qigong therapy in combination with conventional therapy (such as chemotherapy) is a treatment regimen worth recommending.

An analysis of 4628 cases in the genetic counseling clinic of PUMC Hospital is reported. Althogether 966 cases (20.87%) were diagnosed as having genetic diseases, among whom were 436 cases (45.13%) with chromosome aberrations, 161 (16.67%) with inherited metabolic diseases, 111 (11.49%) with constitutional bone diseases, 103 (10.66%) with various kinds of genetic neuromuscular diseases, 109 (11.28%) with different dysmorphic syndromes, and 46 (4.76%) with different kinds of genetic dermatoses and oculopathies. 973 cases (21.02%) were suspected to suffer from some form of genetic disease, but this could not be proved due to a lack of specific diagnostic methods. 2689 cases (58.10%) were found to be unaffected by inherited diseases. Some of the experiences gained and the key role of genetic counselling in family planning are briefly discussed.

A technique for isolating DNA sequences that are likely to be transcriptionally active in both humans and mice has been developed. This method is based on the screening of a human genomic DNA library with single stranded cDNA prepared from late gestation mouse fetal RNA. Using a human chromosome 21 DNA library, we have isolated and characterized two clones which are entirely composed of single copy human DNA sequences and are 2.7 and 6.7 kilobases in length. The 2.7 kilobase clone is homologous to a transcript found predominantly in nonpolyadenylated human fibroblast RNA. It also shows homology to mouse genomic DNA and recognises several polyadenylated RNAs in mouse testis. This cloned sequence has been mapped by in situ hybridization to the distal third of chromosome 21, the region involved in the causation of Down syndrome.

The agouti (a) coat color locus of the mouse acts within the microenvironment of the hair follicle to control the relative amount and distribution of yellow and black pigment in the coat hairs. Over 18 different mutations with complex dominance relationships have been described at this locus. The lethal yellow (Ay) mutation is the top dominant of this series and is uniquely associated with an endogenous provirus, Emv-15, in three highly inbred strains. However, we report here that it is unlikely that the provirus itself causes the Ay-associated alteration in coat color, since one strain of mice (YBR-Ay/a) lacks the provirus but still retains a yellow coat color. Using single-copy mouse DNA sequences from the regions flanking Emv-15 we have detected three patterns of restriction fragment length polymorphisms (RFLPs) within this region that can be used as molecular markers for different agouti locus alleles: a wild-type agouti (A) pattern, a pattern which generally cosegregates with the nonagouti (a) mutation, and a pattern which is specific to Emv-15. We have used these RFLPs and a panel of 28 recombinant inbred mouse strains to determine the genetic linkage of these sequences with the agouti locus and have found complete concordance between the two (95% confidence limit of 0.00 to 3.79 centimorgans). We have also physically mapped these sequences by in situ hybridization to band H1 of chromosome 2, thus directly confirming previous assignments of the location of the agouti locus.

A 23-year-old female was found carrying a submetacentric marker chromosome 14p+. The short arm of the marker chromosome showed a homogeneously stained region in both G-banded and C-banded preparations and was silver-positive in its distal part in AG-NOR preparation. Using a 3H-labelled 7.3 kb fragment of 18S and 28S rRNA genes as a probe and by chromosomal in situ hybridization, it was demonstrated that the autoradiographic silver grains to be located along entire p+ part of the marker chromosome. The short arm of the 14p+ had 5.3 times as many autoradiographic silver grains as that of any other normal acrocentric chromosome, but had no greater NOR activity than did the other acrocentric. The difference of these findings suggested that most of the amplified rRNA genes on the 14p+ chromosome were inactive, they might be inactivated by a process involving DNA methylation.

The physical location of the mouse IFN-alpha locus (Ifa) on chromosome 4 was defined by in situ hybridization of a cloned mouse IFN-alpha probe to metaphase spreads in which one chromosome 4 was present as part of a single metacentric chromosome, all other chromosomes being acrocentric. (This approach greatly facilitates analysis and can be used even when it is difficult to obtain good banding). Using unbanded chromosomes, the grains were localized over the chromosome 4 part of the metacentric, in a region 0.61 +/- 0.07 (SD) of the distance from the centromere to the telomere. In Giemsa-banded spreads, the majority of the grains were in the region 4C3----C6. Consideration of these results and of the known linkage maps for mouse and man indicates that the Galt - Aco-1 - Ifa syntenic group spans a distance of approximately 14 cM and suggests that the same group on human 9p will also occupy a similarly sized region, with GALT proximal and IFL distal to the centromere.