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The paper presents a novel optimal plane arrangement of stabilizing piles in terms of the provided half simplified flattened ellipsoid model, which can be used to describe the three-dimensional characteristics of sliding mass for colluvial landslides. By studying the friction soil arching effect between the adjacent stabilizing piles, a reasonable pile spacing model for stabilizing piles was deduced in consideration of the driving force and shear strength of sliding mass as well as the dimension of pile cross-section. The results indicate that the net pile spacing is in direct proportion to the height of pile cross-section and shear strength parameters of sliding mass, but in inverse proportion to the driving force intensity. Consequently, the net pile spacing should steadily increase from the major slip profile to the profiles near the boundaries accordingly, which can be called the non-uniformly spaced arrangement principle of stabilizing piles for colluvial landslides. In view of the scale factor and groundwater in the different cross sections of landslide, the improved formula of stability coefficient based on the Fellennius method was proposed accordingly. Furthermore, the concept of stability limit was put forward to confine the rational arrangement region for stabilizing piles; consequently, the region beyond the rational arrangement region is not necessary to set piles any more. The case study of the Erliban landslide in the Three Gorges Reservoir Region of China shows that the quantitative optimal plane arrangement scheme based on the proposed reasonable pile spacing model and stability limit only requires 25 stabilizing piles rather than 31 stabilizing piles in the conventional uniformly spaced arrangement scheme, with an obtainable savings of 19.4% in the number of stabilizing piles.

This paper presents an optimization study on the layout and length of anchor cables for stabilizing rock wedges from the perspective of their three-dimensional geological characteristics. On the basis of the generalized geometry model for rock wedges, the expression of driving force of slope at the arbitrary longitudinal section can be deduced by employing the hyperbolic model between driving force and scale factor of rock wedges. Due to the remarkable parabolic characteristics of the driving force expression of rock wedges, a corresponding non-uniform layout principle of anchor cables was proposed, with closer layout in the central part and sparse layout near the side boundaries. The rational length of anchor cables was quantified on the basis of specification and the three-dimensional spatial characteristics of rock wedges. Furthermore, the upper limit spacing of anchor cables was determined by the spacing threshold caused by the parabolic distributed driving force. The spacing distribution of the optimized anchor cables was verified as a parabolic distribution according to a case study on the Shuige rock wedge in Lishui City, China. Compared with the conventional uniform spacing and length design scheme, the adjusted optimal non-uniform scheme can reduce the anchor cables by 16.9 % and 18.9 % in number and in total length, respectively.

Strata consisting of massive, dipping layers of hard rock interbedded with thin, soft interlayers are common in Southwest China, and this structure is conducive to the formation of consequent bedding rockslides. The huge Jiweishan rockslide is an example that mobilized 5.6 million m 3 of massive, lower Permian limestone that was stratigraphically situated above a weak, 30 cm-thick layer of bituminous shale with a downslope dip of 21°. Field data and historical observations indicate that the rupture surface of this rockslide weakened gradually from the rear, upper part to the front. This evidence includes (1) a decrease in the thickness and areal extent of fracture-parallel calcite veinlets along the thin rupture zone. (2) the development of a wide, vertical tension fracture at the upper boundary of the slide block, about 50 years before the catastrophic failure; (3) a succession of small collapses that migrated from the upper to the lower parts of the slide block in the decade before the massive failure. This type of landslide is accordingly termed an advancing consequent bedding rockslide (ACB rockslide). An equation was developed to simulate the mechanical behavior of the rupture surface as a function of position and time. Finally, a computational model that incorporates this equation was used to simulate the evolutionary history using realistic mechanical parameters. The simulation results show how the size of an upper “driving block” progressively enlarges at the expense of a lower “ locking block” that restrains the slide mass, until the locking block becomes so small and weak that failure occurs. Good agreement between the simulation results and field data support the proposed evolution model, including the calculated size of the locking block prior to failure and the width of the upper tension fracture.

The paper presents an improved analytical approach for evaluating the time-dependent stability of colluvial landslides during intense rainfall infiltration. The approach comprises two steps: first to simulate rainfall infiltration and then to compute the safety factor. In terms of the irregularity of the natural landslide surface in implementation of the method, the landslide is divided into several soil slices with approximately straight sides. Each single slice is regarded as a finite slope so that the infiltration formula and safety factor can be deduced. The infiltration formula is derived with combination of the Green–Ampt model and mass conservation law considering seepage perpendicular and parallel to slope surface simultaneously. In the modified infiltration model, both size effect and angle effect are vividly observed in the process of rainfall infiltration into the finite slope, while the former of which is not presented in the original Green–Ampt model. The safety factor is computed using the limit equilibrium method, with the influence of infiltrating water on the shear strength, gravity and seepage force of soil slices considered. By case study of the Shuping landslide in Three Gorges, decline in the safety factor and the decrease in the tendency are definite. Specifically under the rainfall intensity of 50 mm/h, the failure of Shuping landslide is most likely to occur at the time of 102 h. In addition, the results highlight shallow failure along the wetting front under intense rainfall.

Huangtupo landslide, volumetrically the largest, most complex landslide in the Three Gorges Reservoir region of China, is a dangerous mass on which the district of Badong has been inadvertently situated. Risk remediation efforts include the construction of a large observational tunnel and monitoring system that are unique in the world. This tunnel and its side branches permit detailed mapping of its 3D structure while providing samples for laboratory analysis. The new investigations validate that the Huangtupo landslide is a composite of several independent landslides and that movement occurs along the major rupture zones as well as on interlayer sliding zones in the underlying Badong Formation. Uranium–thorium disequilibrium dating establishes that the northern part of the landslide, called the Riverside Slump, underwent at least two periods of movement at about 100 and 40 ka (ka stands for a thousand years). These events were induced by the steep slope created by the downcutting of the Yangzte River. The results from in situ displacement monitoring over a 7-year period confirm that the central part of the landslide is creeping at a slow, relatively stable rate of about 15 mm/year rather than being in a stage of acceleration under the protection of anchored concrete beams and other defense structures at its toe. Available data suggest that engineering measures can control the independent landslides that together constitute the huge Huangtupo mass, which will avoid the need for costly relocation of thousands of people.

The construction of the huge Three Gorges reservoir affected a large region, and the resultant geological and environmental impacts have caused global concern. The remarkable, 30-m annual fluctuation in the reservoir water level poses a significant threat to slope stability in this area. Four hundred sixty-two landslides were identified in the Zigui basin using historical records, satellite images, field investigations and unmanned aerial vehicle (UAV) observations, enabling the construction of a complete landslide database and distribution map. Three failure modes of landslides in the Zigui basin are used to illustrate the major factors that govern reservoir-induced landslides. The results show that (1) > 99% of identified landslides occur on slopes angle 80% occur at elevations below 600 m; (2) Jurassic Niejiashan Formation is highly prone to landslides; (3) Low reservoir levels of 145 m to 155 m greatly reduce slope stability. Based on the information entropy method that use the conditional probability of different influencing factors and principal component analysis as inputs, the relative contributions of various influencing factors are quantified and a landslide susceptibility map was drawn. This susceptibility map helps define the countermeasures that will best reduce fatalities and property losses for areas having different landslide conditions and susceptibilities.

This paper presents a new model of the load sharing law with a three-stage load sharing pattern via a representative case study in the Three Gorges reservoir region, China. A definitive new three-stage load transfer pattern is presented, including end-bearing soil arching, friction soil arching and the sliding mass in front of the pile. By means of the soil arching effect between the anti-sliding pile and landslide mass, the law of the load sharing ratio under different cases, including different intervals, section dimensions, driving forces, and shearing parameters of the sliding mass and the pile-soil interface, is presented by using the explicit finite-difference numerical modelling method. The results show that (a) the effect scale of the soil arching effect is within the scale of four times of the width of the pile; (b) the soil arching only exits within a certain pile interval, and it will become inefficiency beyond the maximum pile interval; (c) there is a threshold value for the cohesion strength parameters of the sliding mass, beyond which the load sharing ratios of soil arching keep in a steady level.

Study question Can the chemokine CXCL6 affect trophoblast cell migration and invasion in human first-trimester placenta? Summary answer Chemokine CXCL6 inhibits trophoblast cell migration and invasion by suppressing matrix metalloproteinase (MMP)-2 activity in human first-trimester placenta. What is known already Several chemokines including CXCL8, CXCL12, CXCL14, CXCL16, CX3CL1, CCL14 and CCL4 can promote or inhibit trophoblast cell migration and invasion in human first-trimester placenta. Study design, size, duration We used the trophoblast cell line HTR8/SVneo cells, primary trophoblast cells and villi explants to investigate the effect of rhCXCL6 on trophoblast cell migration and invasion. Participants/materials, setting, methods First, the CXCL6 RNA transcript level was detected in HTR8/SVneo cells derived from human first-trimester, second-trimester and third-trimester placenta by RT-PCR. Protein expression of CXCL6 and its receptors was tested in first-trimester placenta by immunohistochemistry. Secreted CXCL6 protein was detected in HTR8/SVneo cell supernatants by enzyme-linked immunosorbent assay. Secondly, the effect of rhCXCL6 on HTR8/SVneo cell proliferation was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Thirdly, the effect of rhCXCL6 on cell migration and invasion of HTR8/SVneo cells, primary trophoblast cells and villi explants was tested by transwell migration and invasion assays, respectively. Last, MMP-2 and MMP-9 activity in the supernatants of HTR8/SVneo and primary trophoblast cells treated by rhCXCL6 in the invasion assay was assessed by gelatin zymography. Main results and the role of chance Abundance of the CXCL6 RNA transcript increased with pregnancy development. CXCL6 and its receptor were expressed in several cells at the human maternal-fetal interface. RhCXCL6 inhibited trophoblast cell migration and invasion by suppressing MMP-2 activity. Limitations, reasons for caution These experiments are only in vitro. Wider implications of the findings According to the literature, CXCL6 could promote tumour cell migration and invasion by accelerating MMP-9 activity. However, CXCL6 inhibited trophoblast cell migration and invasion by suppressing MMP-2 activity in human first-trimester interface. These data suggest that strict regulation of CXCL6 is required for normal migration and invasion of cells, such as those involved at the maternal-fetal interface.

Long-distance natural gas transmission pipelines are planned to pass through the mountain area of midwest China, portions of which are threatened by severe landslide hazards. Therefore, the protection plan and control scheme for pipelines traversing and/or exiting landslide areas are of increasing interest and importance. A typical landslide in western China was used as an example to implement the strategy and evaluate the safety for a typical underground pipeline crossing the landslide area. The investigation and resulting control measures are based on the engineering geological study, and the numerical (finite-difference) interactive model of the pipeline and landslide, including the effect of soil arching. The effect of key design factors, including the spacing of antisliding piles, is determined by three-dimensional finite-difference numerical modeling. This technique also calculates the stability coefficient by use of the strength reduction method and calculation of stress and displacement fields. The results show that the recommended deployment of the antisliding piles can dramatically improve stability by reducing the effect of the landslide, thereby maintaining the displacement and stress of the pipeline within acceptable limits.

Yangjia Shan instability has been evidenced by the occurrence of the July 16, 1997 landslide. The instability factor which leads to activating the landslide is the intense rainfall; lithology of Luoreiping Formation and the highly weathered slopes’ rocks have played a great role in starting and aggravation. Weathering at the landslide site consists largely of attack on the cement and removal of support of the sandy mudstone and sandstone and decompose of shale. The weathering degree of the rocks decreases vertically with increasing depth from high, medium to slightly weathered corresponding to grade IV, III and II, respectively. The slip surface consists of moderate to highly weathered intercalated layers of sandy mudstone (mudstone) and shale, while, the layer below the slip surface is characterized by dark gray, moderately weathered and thick layered mudstone. The moderate to highly weathered subsurface lithology is probably attributed to the accumulation of the infiltrated rainfall water through fractures and porosity, raising the ground water level and wetting of the sandy mudstone and shale rocks of Luoreping Formation. The wetting contributed more or less to the disintegration of the sandy mudstone and shale, lowered the shear strength and created cracks on the upper part of the slope leading thus to increase the landslide susceptibility. Therefore, the frequency and magnitude of landslide at the study area and its vicinity are expected to increase through the activation of old landslides and triggering of new ones under circumstances similar to those of the past.

In the present study, we evaluated the diagnosis and management modalities of caesarean scar pregnancy (CSP). Thirty patients diagnosed with CSP were retrospectively studied between February, 2010 and February, 2012. Twenty-five patients were offered prophylactic uterine artery embolization (UAE) and methotrexate (MTX) prior to uterine suction curettage. Five cases were referred from other hospitals where the initial management with uterine suction curettage had resulted in uncontrollable massive haemorrhage, 4 of the cases had UAE and one proceeded immediately to hysterectomy. In the 25 patients treated with prophylactic UAE and MTX, 12 had laparoscopy-guided curettage and 13 had ultrasound-guided curettage without complication. The results showed that the 25 patients with CSP, who received prophylactic UAE and MTX prior to uterine curettage, recovered without complications. Five patients referred from other hospitals, where uterine curettage was the primary procedure, had severe complications including uncontrolled vaginal bleeding and uterine rupture. Four of the five patients were treated successfully with emergency UAE and the remaining patient underwent emergency hysterectomy as ultrasound examination detected significant haemorrhage between the uterus and the bladder. Of the 25 patients who received prophylactic UAE combined with MTX, there were no reports of irregular menstruation or serious adverse effects. Notably, the decrease in serum human chorionic gonadotropin (HCG) levels 3 days post-surgery was greater with ultrasound-guided curettage (84.3±5.5%) than with laparoscopy-guided curettage (76.3±10.2%). In summary, the data suggested that prophylactic UAE with MTX followed by ultrasound-guided curettage is the most effective therapeutic approach in CSP.

This paper develops a new method to directly determine the composite elastic modulus of the reinforced con­crete cantilever pile rather than adopt theoretical or empirical approaches. On the basis of the theory of material mecha­nism, the load-deflection equation was deduced to create the relationship between the elastic modulus and the ratio of load-deflection. The numerical modelling tests based on ANSYS separation modelling technology were carried out to determine the composite elastic modulus under different reinforcement ratio, concrete strength grade and distribution pat­tern of driving force. The results can be used to create the quantitative relationship between the composite elastic modulus and reinforcement ratio as well as concrete strength grade. Comparison amongst various lateral load pattern were made to show that the deflection of pile head is obviously affected by the lateral load pattern, and the corresponding equations of the deflection of the pile head under different lateral load pattern were proposed, which can reflect the ranking of the great influence on the deflection of the pile head, rectangular, trapezoidal and triangular lateral load pattern in order. First published online: 24 Aug 2015

The stratified rock of Jurassic strata is widely distributed in Three Gorges Reservoir Region. The limit equilibrium method is generally utilized in the stability analysis of rock slope with single failure plane. However, the stratified rock slope cannot be accurately estimated by this method because of different bedding planes and their variable shear strength parameters. Based on the idealized model of rock slope with bedding planes, a modified limiting equilibrium method is presented to determine the potential sliding surface and the factor of safety for the stratified rock slope. In this method, the S-curve model is established to define the spatial variations of the shear strength parameterscand φof bedding plane and the tensile strength of rock mass. This method was applied in the stability evaluation of typical stratified rock slope in Three Gorges Reservoir Region, China. The result shows that the factor of safety of the case study is 0.973, the critical sliding surface for the potential slip surface appears at bedding plane C, and the tension-controlled failure occurs at 10.5 m to the slope face.

After the normal operation of the Three Gorges Reservoir, the water level of the reservoir will fluctuate periodically. Water level fluctuation will soften the rock and soil on the banks, induce underground water fluctuation and decrease the shear strength of rock soil on the banks, and in turn affect the landslide stability. The Huangtupo (黄土坡) landslide is a typical large and complex landslide in the Three Gorges Reservoir region. In particular, the stability of its riverside slumping mass has a great stake. On the basis of the analysis of engineering geological condition and formation mechanism of the Huangtupo landslide, the authors established the 2D finite element model of riverside slumping mass II# and selected proper mechanical parameters of the rock. With the GeoStudio software, according to the reservoir running curve, the simulation on coupling effect of seepage field and stress field was conducted in 7 different modes in a year. The results showed that: ➀ Huangtupo landslide is a large and complex landslide composed of multiple slumping masses, which occurred at different phases. Before reservoir impoundment, it was stable; ➁ it is quite difficult for riverside slumping mass I# and II# to slide as a whole; ➂ the stability coefficient of riverside slumping mass II# changes with the reservoir water level fluctuations. The minimum stability coefficient occurs 48 days after the water level starts to fall and the moment when the water level falls by 11.9 m. Landslide monitoring result is consistent with the numerical simulation result, which shows that although the reservoir water level fluctuation will affect the foreside stability of the landslide and induce gradual damage, the riverside slumping mass II# is stable as a whole.

During the monitoring engineering of landslides, the monitoring data of accumulated displacement are usually affected by the external factors. Therefore, the displacement curve always has step-like character, which brings some difficulties to the accurate prediction of landslides. In order to solve this problem, based on the wavelet analysis and cusp catastrophe, a new kind of analysis method is proposed in this article. First, Fourier transform method can be used to extract the frequency component of the curve of monitoring displacement. Second, the wavelet transform was adopted to inspect the breakpoints of signals, which can be used to analyze the cause of the occurrence of the step-like character in the curve of landslide monitoring. Based on the cusp catastrophe theory, a nonlinear dynamic model was established to conduct the simulation calculation of time forecasting of landslides. According to a case study of landslide, the periodical rainfall and reservoir level fluctuation are the main factors leading to the step-like changes in the curve of monitoring displacement. In addition, the results of simulation calculation are in agreement with the fact of local failure of landslides. This method can provide a new analysis way for the time prediction of landslides.

Cervical intraepithelial neoplasia (CIN) is a precancerous disease of cervical squamous cell carcinoma. We Used Mass Spectrometry based peptidome profile study to predict the transformation of CIN1, which is the primary stage of this lesion. . Serum samples of 34 Cervical squamous cell carcinoma patients, 31 healthy controls, and 29 CIN1 samples were analyzed. Peptides were purified by WCX magnetic beads (Bioyong), and analyzed by MALDI TOF (Bruker). Raw data were analyzed by BioExplorer software (Bioyong). The results showed 14 mass peaks with significant differences. The diagnosis model is established by analyzing peptide profiles of 15 SCC patients and 20 healthy women serum, with a sensitivity of 100% and specificity of 100.00%. In validation set, the SCC diagnosis model also had good performance with a sensitivity of 80%, a specificity of 100%. In addition, this model could predict 29 CIN1 patients with accuracy of 55.17%. These results would provide a new method to predict the trend of CIN1 and take effective measures for high risk group timely.

Scanline observation is known to introduce an angular bias into the probability distribution of orientation in three-dimensional space. In this paper, numerical solutions expressing the functional relationship between the scanline-observational distribution (in one-dimensional space) and the inherent distribution (in three-dimensional space) are derived using probability theory and calculus under the independence hypothesis of dip direction and dip angle. Based on these solutions, a novel method for obtaining the inherent distribution (also for correcting the bias) is proposed, an approach which includes two procedures: 1) Correcting the cumulative probabilities of orientation according to the solutions and 2) Determining the distribution of the corrected orientations using approximation methods such as the one-sample Kolmogorov-Smirnov test. The inherent distribution corrected by the proposed method can be used for discrete fracture network (DFN) modelling, which is applied to such areas as rockmass stability evaluation, rockmass permeability analysis, rockmass quality calculation and other related fields. To maximize the correction capacity of the proposed method, the observed sample size is suggested through effectiveness tests for different distribution types, dispersions and sample sizes. The performance of the proposed method and the comparison of its correction capacity with existing methods are illustrated with two case studies.

In the flight of hypersonic near space vehicle from 60km up to 100km high, the influence of real gas effect, rarefied gas effect, and Mach number effect cannot be simulated completely by the ground test. In this paper, the selection of computational model is introduced, and then carried out the numerical research on slip flow field characteristics coupling with chemical-equilibrium effect under large Mach number of high altitude.

To estimate cesarean delivery rates and indications by region in mainland China.A cross sectional survey of all deliveries in 39 hospitals in 14 provinces of mainland China from January 1 to December 31, 2011 was evaluated for mode of delivery, cesarean delivery rates and indications for delivery.(1) A survey of a total of 112 138 women at delivery with gestations greater than 24 weeks was analyzed. 79 631 and 32 507 deliveries were obtained from the tertiary and secondary hospitals respectively. 90 971 were primipara, 21 167 were multipara. Of these pregnancies, 61 084, 49 734 and 1 320 cases resulted in cesarean delivery, vaginal delivery and operative vaginal delivery respectively, the cesarean delivery rate was 54.472% (61 084/112 138). Among 61 084 women who had cesarean delivery, 14 998 cases of the cesarean deliveries were performed without medical indications, 46 086 cases of the cesarean deliveries had medical indications. The cesarean delivery rate of the tertiary hospitals was 55.927% (44 535/79 631), and was significant higher than that in the secondary hospitals (50.909%, 16 549/32 507; P0.01). (2) Overall 24.553 % (14 998/61 084) of cesarean deliveries were performed without medical indications. 19.744% (8 793/44 535) of the cesarean deliveries without medical indications were performed in the tertiary hospitals, and was significant lower than in the secondary hospitals (37.495%, 6 205/16 549;P0.01). (3) Maternal request was the most common indication (24.553% of all cesarean deliveries), followed by fetal distress (12.507% , 7 640/61 084), cephalopelvic disproportion (11.787%, 7 200/61 084), previous uterine surgery (10.374%, 6 337/61 084), malpresentation (5.815%, 3 552/61 084), failure to progress (5.710%, 3 488/61 084) and suspected macrosomia (5.594%, 3 417/61 084).The increasing caesarean section rate in mainland China is explained mainly by the high non-indicated caesarean section rate. The main medical indications of the cesarean deliveries included fetal distress, cephalopelvic disproportion, previous uterine surgery, malpresentation and failure to progress.

Choosing the reasonable depths of a buried pipeline is one of the crucial issues for long-distance gas transmission pipelines. This paper focuses on the mechanical analysis of a pipeline with a different buried depth under the driving force of a landslide. The relationship between the bending moment, shear force, displacement and buried depth of pipeline can be derived under certain assumed conditions. The result of the Zhong County-Wuhan City gas transmission pipeline project shows that the moment reaches a greater value at the junction and the midsection of the pipeline and the shear force reach maximum at the junction along with the increase of buried depth of the pipeline. On the basis of the stress characteristics of deep-buried pipeline in engineering practice, it can improve the safety of a gas transmission pipeline by enhancing the piping material performance at the junction and the middle part of the pipeline.

To study the differences immune function in normal cervix, cervical intraepithelial neoplasia (CIN) and cervical cancer tissue, and study the relationship between human papillomavirus (HPV) infection and cervical local immune function.This study determined the form, quantity, distribution, and intensity of CD4+Th cells, S-100+ dendritic cells (DCs) and CD57+NK cells in the normal cervical tissue, CIN cervical tissue, and cervical cancer by histopathological and image analyses.The immune function was differences in the progress of cancer genesis. The numbers of the CD4+ Th cells, S-100+ DCs, and CD57+NK cells increased with the progress of the disease in CIN, but when cancer occurred, immune cells decreased in local cervical tissue.From lesion precancerous to infiltrating carcinoma, the form, quantity, and intensity of expression of immune cells changed, which may indicate that the cervical local immune function has changed. Furthermore, high-risk HPV infections are more active in local immune function.

Chemokines and chemokine receptors have been implicated a pivotal role in trophoblast differentiation and in the formation of a functionally normal placenta. In this study, we present data that highlight the involvement of chemokine ligand 17/chemokine receptor 4 (CCL17/CCR4) expression at the fetomaternal interface and expand its biological relevance of influence during trophoblast differentiation and placentation. By immunohistochemistry, we found that CCL17 was abundantly expressed in the decidua and trophoblasts, especially in cell columns. The receptor for CCL17, CCR4, was specifically expressed in invading interstitial extravillous trophoblasts. Furthermore, by transwell migration, invasion assays, and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, we found that exogenous CCL17 concentrations paralleled the invasive potential of cytotrophoblasts to some extent, with no significant effect on cell proliferation. Using Western blotting, we demonstrated that the stimulatory effect of CCL17 was related to the expression of matrix metalloproteinase 2 (MMP-2), MMP-13, integrin α5, and integrin β1, although it downregulated tissue inhibitors of MMP-1 expression. In conclusion, our findings suggest that CCL17, as a differentiation-related molecule coexpressed by decidua and trophoblast, stimulates extravillous trophoblast migration and directs invasion mainly via modulating integrins, MMPs, and its inhibitor levels.

Hypertensive disorders of pregnancy (HDP) are a group of medical complications in pregnancy and also a risk factor for severe pregnancy outcomes, but it lacks a large-scale epidemiological investigation in recent years. This survey represents a multicenter cross-sectional retrospective study to estimate the prevalence and analyze the risk factors for HDP among the pregnant women who had referred for delivery between January 1st 2011 and December 31st 2011 in China Mainland. A total of 112,386 pregnant women were investigated from 38 secondary and tertiary specialized or general hospitals randomly selected across the country, of which 5,869 had HDP, accounting for 5.22% of all pregnancies. There were significant differences in the prevalence of HDP between geographical regions, in which the North China showed the highest (7.44%) and Central China showed the lowest (1.23%). Of six subtypes of HDP, severe preeclampsia accounted for 39.96%, gestational hypertension for 31.40%, mild preeclampsia for 15.13%, chronic hypertension in pregnancy for 6.00%, preeclampsia superimposed on chronic hypertension for 3.68% and eclampsia for 0.89%. A number of risk factors for HDP were identified, including twin pregnancy, age of >35 years, overweight and obesity, primipara, history of hypertension as well as family history of hypertension and diabetes. The prevalence of pre-term birth, placental abruption and postpartum hemorrhage were significantly higher in women with HDP than those without HDP. The possible risk factors confirmed in this study may be useful for the development of early diagnosis and appropriate treatment of HDP.

Long-distance natural gas transmission pipelines are designed to cross the large-scale mountain area with the start of the West-East Gas Pipeline Project in China. A great portion of the pipelines are now threatened by severe landslide hazards. The pipeline could fail resulting in a great loss because of the landslide failure deformation. Therefore, the spatial arrangement plan of pipeline underground crossing landslide area is one of the key problems. The paper presents a new mechanical model of pipeline and landslide under trapezoidal landslide force to conduct the mechanical analysis on deformation of pipeline. A series of shear force, bending moment and defection of pipeline under landslide with different crossing angle can be deduced according the simplified model presented. Based on a case study of a typical landslide with pipeline underground crossing, the geological mechanical model of landslide and pipeline system can be established. The mechanical characteristics of pipeline can be conducted under the driving force of landslide by utilizing mechanics theory so as to determine the position of maximum stress point along the pipeline. Consequently, the optimal crossing depth and orientation of pipeline can be obtained. The result shows that the proper setting of crossing angle and buried depth can effectively improve the safety of pipelines. The corresponding control strategy suggestions for similar pipeline projects are proposed as well.

Objective: To examine the treatment of previous cesarean delivery scar defect after cesarean delivery and the feasibility of laparoscopic uterine repair or hysteroscopic scar excision. Study Design: A retrospective clinical study that took place from June 2009 to March 2013 and included 41 women who had previously had cesarean deliveries. Results: Seventeen women underwent a laparoscopic approach for the repair of scar diverticula, and 24 women underwent a hysteroscopic resection of fibrotic tissue overhanging underneath the diverticula. Most women remained free of symptoms over a 3- to 16-month follow-up and 6 women became pregnant without pregnancy complications. Conclusion: Women with a history of cesarean delivery combined with irregular perimenstrual bleeding should undergo combined hysteroscopy and ultrasound examination to detect latent scar defects. In diagnosed cases, in those who desired future pregnancies and had a residual myometrial thickness of

The horizontal foundation coefficient of pile hole walls is a key factor in the design and maintenance of stabilizing piles. An automatic bearing plate-loading test apparatus was developed to measure the horizontal foundation coefficient of a pile hole wall based on an in situ test. The apparatus has an integral structure, providing two switchable loading modes, i.e., a displacement-control mode and loading-control mode, and all functional parts are integrated into a removable unit. The loading frame is controlled by a proportion integration differentiation closed-loop controller, and its rigidity compensation is considered if a transmission column is used for the large span. The process of the field test is described, including the selection of the test location, preparation of the test hole and operation of the test apparatus. The corresponding relationships between the displacement-foundation coefficient (S-K) curves and the deformation and failure stages of the rock mass during the test are analysed. The accuracy of the test results is assessed via comparison with the corresponding rock layer in the current specification.

To determine the prevalence and factors associated with histologic diagnoses of cervical intraepithelial neoplasia in women with ASC-US.Sampling investigations were carried out on married women aged 25-54 in 12 districts in Beijing from April 2007 to November 2008. Further examinations and analyses were carried out on women with ASC-US in the cytological screening.Of 6,339 women, 9.6% suffered from cervical abnormalities in cytology; among them, 409 cases were ASC-US. Of the 409 ASC-US, 42.1% showed inflammation; 50.9% had CIN 1, 6.1% had CIN 2, and three cases had CIN 3, one of which was cervical cancer. Four hundred and four cases were subjected to detection for the human papillomaovirus (HPV) and the infection rate was 30.7%. Morbidity in the HPV infected patients that suffered from CIN 2 or higher was significantly higher than that in the uninfected population (chi2 = 26.685, p = 0.000). No statistical significance was found in the correlation between the pathological results of ASC-US and the loading dose of HPV infection (chi2 = 7.754, p = 0.458).The morbidity of CIN in women with ASCUS in Beijing is high, and women with ASC-US should be paid great attention, especially women who are infected with high-risk HPV.

To evaluate the value of the loop electrosurgical excision procedure (LEEP) for repeat low-grade squamous intraepithelial lesions (LSIL) with unsatisfactory colposcopy and the outcomes of postconization.We performed LEEP in 136 patients and followed them up with colposcopy, cytology, and high-risk HPV (HR-HPV) detection using Hybrid Capture II (HCII).55.1% of women had CIN 1 in the specimen, 17.6% had CIN 2-3, and 27.2% had no lesion. The sensitivity of detecting persistent/recurrent disease can reach 90.9% when positive post-treatment HR-HPV or first abnormal cervical cytology after LEEP are found, and the specificity is 95.3% when positive post-treatment HR-HPV coexisting with first abnormal cervical cytology after LEEP are detected.Repeat LSIL with unsatisfactory colposcopy implies a significant risk of CIN 2-3. LEEP is a rational option to those patients with high-risk HPV infection or dysplastic endocervical curettage. Post-treatment follow-up of patients should include both cytology and HR-HPV testing.

With the starting of the West-East Gas Pipeline Project recently, the hazard evaluation of underground crossings of landslide areas has become of increasing interest within China as well as overseas. Due to landslide failure deformation, the pipeline could fail resulting in a great loss. Therefore, the arrangement plan of pipeline underground crossing landslide area is one of the key problems. A typical landslide in Western China area was taken as an example, from which the interaction model of landslide and pipeline was established. On the basis of the geotechnical finite difference software FLAC 3D , by using the mechanical analysis and numerical modeling, several schemes with different positions and different buried depths of pipeline were presented in order to carry out a comparative analysis and study. The results show that the pipeline in the front part of the landslide bears the smallest pressure and the maximum stress of pipeline increases with the increase of the buried depth of the pipeline. Therefore, the pipeline with shallow buried depth in the front part of the landslide is best route choice for the pipeline across the landslide, where the pipeline bears the smallest pushing force by the landslide. As a result, the method of choosing optimal position for the pipeline can reduce the geological hazard risk to the maximum extent. This study can provided a scientific basis for the pipeline route selection scheme in underground crossing landslide area of Western China.

This study presents a genetic algorithm GA adopted for recognizing the material parameters with the nonlinear relation in the sheet metal forming. Firstly the nonlinear regression model is established for the parameters estimation. Then based on the material tensile test the parameters estimation is finished by GA and the least square method LS. At last GA is applied for recognizing the material model parameters and the numerical simulation is finished in the V-shape sheet metal forming.

Objective To survey the proportion of births born after assisted reproductive technology (ART) and compare the obstetric and prenatal complications between ART and spontaneous pregnancy in women in mainland China. Design Retrospective analysis. Setting Thirty-nine hospitals. Patient(s) A total of 112,403 deliveries from 14 provinces and 39 different hospitals composed our retrospective study. Intervention(s) A multiprovince, hospital-based survey was performed. Main Outcome Measure(s) The prevalence of obstetric complications, mode of delivery, and prenatal outcomes were compared between ART and spontaneous pregnancy. For each group, data included singleton and twin deliveries. Result(s) The proportion of infants born as a result of ART in mainland China was about 1.013% in 2011. The incidence of hypertensive disorder in pregnancy (11.0%, odds ratio [OR], 1.27, 95% confidence interval [CI] 1.04–1.60), premature delivery (27.0%, OR, 4.53, 95% CI 3.91–5.25), gestational diabetes mellitus (15.1%, OR 3.05, 95% CI 2.57–3.60), and placenta previa (4.5%, OR 2.18, 95% CI 1.62–2.94) were markedly increased in women who conceived using ART. The cesarean section rate in the ART pregnancy group was 85.3%, which is significantly higher than spontaneous pregnancies (54.0%). Compared with spontaneous pregnancy, ART pregnancy had a significantly increased incidence of low birth weight babies (29.7%) and birth gestational age of less than 37 weeks (30.0%). Infants conceived by ART have increased low 5-minute Apgar and mortality. Conclusion(s) This population-based survey demonstrates that the proportion of births from ART in mainland China was about 1.013% in 2011. Multiple gestation is significantly increased in ART pregnancies, relative to spontaneous pregnancies. The increasing incidence and risk of maternal complications in ART pregnancies (e.g., premature delivery, placenta previa, gestational diabetes mellitus) are found in singleton and twin gestations in ART. A higher cesarean section rate, low birth weight infants, and higher infant mortality rate were also observed in ART pregnancies. Our survey provides a comprehensive overview of the prevalence of ART and ART-associated complications in mainland China, and provides insight into attitudes toward ART among the mainland Chinese population.