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The effect of different initial degrees of saturation on the behaviour of variably saturated soils around an expanding cavity has not been adequately studied thus far. Therefore, this study aimed to fill this gap. Moreover, it sought to theoretically explain the cylindrical cavity expansion response in unsaturated three-phase media, particularly focusing on its effect on the cavity wall during the transition from an unsaturated to a saturated state. To this end, a semi-analytical solution based on a hydro-mechanically coupled Sheng–Fredlund–Gens model was proposed for the undrained cavity expansion problem in variably saturated soils in which unsaturated and fully saturated regions coexisted around the cavity. The cylindrical cavity expansion and expansion pressure response in initially unsaturated soils (considering different initial degrees of saturation) and initially fully saturated soils were explored. The proposed solution further extends the cavity expansion theory to unsaturated soils. Furthermore, this work could serve as a theoretical framework for modelling of the cavity expansion problem in the variably saturated soils considering the effect of hydraulic state transition.

Objective: To explore the expression of cyclophilin A (CypA) in esophageal tissues and its clinical significance. Method: Expression of CypA was detected in 236 esophageal cancer tissues and 236 normal tissues by using an immunohistochemical method, and the relationship between CypA expression and clinical outcomes was observed. Results: There were 166 patients with high expression of CypA (70.23%) and a higher expression in 69.3% of males and 73.3% in females. The CypA expression was irrelevant to age, tumor location, lymph node metastasis, and tumor differentiation degree. The Kaplan–Meier survival curve analysis showed that the expression of CypA was associated with the prognosis of patients with esophageal squamous cell carcinoma. Conclusion: The poor prognosis of esophageal cancer patients was associated with high expression of CypA.

This paper aims to reveal the mechanical effects of metal holder and bolt (anchor) in anchor frame combination structure, then shows existing problems of anchor frame combination supporting structure being used in present coal mine, and gives corresponding solution on the basis of modern mechanics theory. By specify examples and on the basis of having administered the pull test of bolt (anchor), the article has calculated and analyzed the stress distribution rule of metal holder in anchor frame combination supporting structure according to the statically indeterminate principle in solid mechanics. In contrast to single metal holder structure, the consequence comes to be that the bearing capacity was significantly increased. However, the actual stress values of bolt (anchor) in field measurement shows that the bearing capacity of bolt (anchor) has hot been given full work. So the essay not only reveals the good bearing capacity of anchor frame combination structure but also points out that there is plenty of scope for optimization in anchor frame combination structure, and its research results have a certain reference for supporting theory and technology research in deep level and high ground pressure soft rock roadway.

Through the mould contrasting experiments the carrying capacities and deformation effects of surround rock with different underground roadway arrangements are studied in this paper. On the basis of experiment measuring results the bearing capacities and strains of surround rock moulds in different stratum roadways and arrangement positions are obtained. It is shown that underground roadway positions in weak rock stratum can bring about more decrease in surround rock bearing capacities and the positions below weak stratum can have high bearing capacity under the high ground pressure actions. The roadway horizontal space enlarging one times may increase more 25% bearing capacities of surround rock for rock or weak stratum roadway. The dislocation arrangements of roof roadway with below weak stratum roadway can improve about 41.5% bearing effects and have a little deformation of surround rock. The research conclusions are important significance of conducting for reasonable designing underground roadway engineering.

Treating surrounding rock as absolutely loose mass helps to determine positions of the four key reinforced points in roadway, in other words, they are juncture locations between 45 degrees angle directions of two arch haunches and two footwalls. Surrounding rock deformation can be effectively controlled with the help of reinforcement on key reinforced points, furthermore, it is possible to save lots of supporting materials, in short, it is a very effect way. New technology proposed in this paper what is about stable augmentation has deeply unearthed important effect of anchor in floor of roadway, it argues that anchor in floor has quadruplex efficacies: transferable effect of surrounding rock stress, displacement boundary effect, decreasing equivalent stress of basic angle area and the inverted wedge effect, so it can suppress floor heave effectively, and this lays a solid foundation for roadway stability. Article deeply analyzed basic mechanism about deformation of roadway under loading, exposed essentiality of roadway support, and provided important theoretical basis for floor heave control emerged more and more frequently in deep mine roadway. Key words: broken rock zone, bolt support, floor heave, equivalent stress

This paper synthetically analyzed essential features of various support methods in engineering geological soft rock, proposed a scheme that organically combines active support (like anchor bolt support) with passive support (like U-shaped steel bracket support), analyzed fundamentals of this combined support scheme, and forecasted support effect of this support scheme. It provides roadway support design with fresh ideas. U-shaped steel bracket can be translated into special anchor plate with the help of a section of simple steel channel beam, so effect of anchor bolt can be ensured; U-shaped steel bracket , this extremely long curved beam ,will be divided into several sections of short beams, so its bearing ability will be several times improved. Cost of this combined support scheme is low, its process is simple and its application prospect is wide.

Floor grouting in soft rock roadway is one of the effective ways in floor heave control, and this method is being promoted quietly and quickly, but the applying effect is far from satisfied, the reasons are that: the depth of floor grouting is not enough and the influence of water hiding in floor hasnt been attached great importance. This paper analyzed the characteristics of floor broken rock zone in soft rock roadway and pointed out the importance of floor grouting in soft rock roadway, then proposed a practical method of floor grouting. The analysis conclusions show that: the depth of floor broken rock zone that can reach more than 4m is much greater than that of roof broken rock zone due to the double influences of surrounding rock stress and water; the important role of floor grouting in soft rock roadway is draining off free water from broken rock zone in order to strengthen roadway floor; floor grouting includes three important steps: plugging water channels, pumping out free water and grouting in deep holes. The article has revealed common blind spots of floor grouting methods existing, the method this article has noted can solve floor heave of soft rock roadway well, and it has very good application prospects. Key words: soft rock roadway, floor grouting, broken rock zone, free water in floor

A three-dimensional nonlinear elastic-plastic finite element method had been developed to study the bending behavior of piles subjected to axial load and lateral soil displacement. The influence of the lateral soil displacement, axial load level and the cap of piles were studied and variety law of the bending behavior was presented. The study showed that the bending moment increased with the lateral soil displacement. The displacement at the soil surface and the maximum bending moment of pile also increase with the axial load. The cap of piles has a great influence on bending moment and displacement of pile group.

The purpose of this study was to detect the feasibility, safety, and effectiveness of mediastinoscopic esophagectomy for early esophageal cancer.The clinical data of 194 patients who underwent mediastinoscopic esophagectomy for early esophageal cancer in our center from December 2005 to October 2014 were retrospectively analyzed.All the surgery was performed successfully. The average duration of thoracic surgery was 48.2±7.8 min and the average intra-operative blood loss was 128.1±34.5 mL. An average of 3.1±1.6 lymph node stations were dissected, with an average number of dissected lymph nodes being 9.38±6.2, among which 4.2±5.4 were mediastinal lymph nodes. No peri-operative mortality was noted, and the rate of peri-operative morbidity was 13.4%. The median duration of follow-up was 39 [3-108] months, and the overall survival was 72.73%. The overall survival rates significantly differed among different T stages; more specifically, the 5-year survival was 95.23% in patients with stage T1a esophageal cancer, 70.15% for T1b, and 55.56% for T2 (P0.001). The overall survival was significantly better in patients with negative lymph nodes than those with lymph nodes metastasis (P=0.003); more specifically, the 5-year survival rate was 84.9% for N0, 62.5% for N1, and 50.0% for N2 + N3.The mediastinoscopic esophagectomy can achieve a similar effectiveness as the conventional thoracoscopic surgery for patients with early stage esophageal cancer.

To explore the safety of video-assisted thoracoscopic esophagectomy for esophageal carcinoma.From January 2005 to March 2012, 260 patients with esophageal carcinoma received thoracoscopic esophagectomy (TE group), while 322 patients underwent conventional open esophagectomy (OE group). Operative procedures, perioperative complications, reoperation, readmission to intensive care unit (ICU), and perioperative mortality were compared between the two groups.Compared with OE group, TE group possessed less thoracic operative time [(105±30) min vs. (112±41) min, P=0.000], less blood loss [(95±48) ml vs. (107±44) ml, P=0.002], shorter postoperative hospital stay [(14.3±7.5) d vs. (16.9±9.5) d, P=0.000] and more lymph node harvest from thorax [(13.5±5.0) vs. (11.6±4.7), P=0.000]. The total perioperative complication rate was lower in TE group than that of OE group (34.6% vs. 45.0%, P=0.011), as well as perioperative mortality (0.8% vs. 3.4%, P=0.032). Lower rate of readmission to ICU (5.4% vs. 10.6%, P=0.024) was found in the TE group as compared to the OE group, while the reoperation rate was comparable (1.5% vs. 2.5%, P=0.425).Thoracoscopic esophagectomy is advantageous than open procedure in terms of surgical safety.

During the penetration process of jacked pile installation, the soil around pile will move laterally and heave. The existing structures and facilities were often damaged due to the soil movement resulted from jacked pile installation. To reduce those accidents, it is important to study the law of the lateral soil movement and upward heave due to compaction. This paper describes results from a series of experiments that investigated the radial soil displacement due to jacked piles in layered soils. A number of jacked piles were installed in a test chamber filled with dry sand and rubber powders, which was used to simulated soft soil. Closed-ended piles with 40-mm diameters were used. The experiments were carried out to study how radial displacement and vertical displacement changed as the pile penetration depth varied. We determined how the displacement value changed at different soil interfaces during the pile pressing process. The results revealed the soil displacement behavior produced by different position and penetration depth of the pile. We found that a lag effect existed between the maximum displacement and the pressed pile depth. The experimental results allow for a better understanding of the inherent mechanism of compaction of the jacked pile during the penetration process. These results are important for estimating the influence of pile installation and guiding jacked pile design.

In the urban environment, pile foundations are frequently constructed in locations very close to existing tunnels. The influence of bored piles on existing tunnels is a common interaction problem especially in soft ground. In order to further the understanding of the influence of bored pile construction on existing tunnels, a FLAC3D computational model was conducted. The applicability of the presented model was verified with certain field case histories. Soil displacements, tunnel deformations and tunnel lining bending moments due to the bored pile construction were analyzed. The results show that the bored pile construction should not be ignored in the analysis of the influence of bored piles on adjacent tunnel. ABSTRACT: In the urban environment, pile foundations are frequently constructed in locations very close to existing tunnels. The influence of bored piles on existing tunnels is a common interaction problem especially in soft ground. In order to further the understanding of the influence of bored pile construction on existing tunnels, a FLAC3D computational model was conducted. The applicability of the presented model was verified with certain field case histories. Soil displacements, tunnel deformations and tunnel lining bending moments due to the bored pile construction were analyzed. The results show that the bored pile construction should not be ignored in the analysis of the influence of bored piles on adjacent tunnel.

Bearing capacity of rectangular footings was simulated with three-dimensional finite difference program. In the analysis, soil is modeled using Mohr-Coulomb model. Shape effects on bearing capacity of rectangular footing are evaluated without using the conventional superposition. To avoid error induced by superposition, cohesion and soil unit weight are normalized as one parameter. Numerical results show that bearing capacity of rectangular footing decreased with the increase of footing aspect ratio. The effects of footing shape are also different with the characteristics of soil. In general, effects of footing shape are more obvious for soils with high cohesion, while they are slight on soils with low cohesion.

AIM: To define the benefits of three-dimensional video-assisted thoracoscopic esophagectomy (3D-VATE) over 2D-VATE for esophageal cancer. METHODS: A total of 93 patients with esophageal cancer including 45 patients receiving 3D-VATE and 48 receiving 2D-VATE were evaluated. Data related to patient and cancer characteristics, operating time, intraoperative bleeding, morbidity and mortality, postoperative inflammatory markers, Numerical Rating Scale for postoperative pain, Constant-Murley rating system for shoulder recovery and oxygenation index (OI) were collected. All medical records were retrieved from a prospectively maintained oncological database at our institution. A retrospective study was performed to compare the short-term surgical outcomes between the two groups. RESULTS: No significant differences were found between the two groups in either morbidity or mortality (P = 0.328). An enhanced surgical recovery was noted in the 3D group as indicated by shortened thoracoscopic operation time (3D vs 2D: 68 ± 13.79 min vs 83 ± 13 min, P < 0.01), minor intraoperative blood loss (3D vs 2D: 68.2 ± 10.7 mL vs 89.8 ± 10.4 mL, P < 0.01), earlier chest tube removal (3D vs 2D: 2.67 ± 1.01 vs 3.75 ± 1.15 d, P < 0.01), shorter length of hospital stay (3D vs 2D: 9.07 ± 2.00 vs 10.85 ± 3.40 d, P < 0.01), lower in-hospital expenses (3D vs 2D: 74968.4 ± 9637.8 vs 86211.1 ± 8519.7 RMB, P < 0.01), lower pain intensity (P < 0.01) and faster recovery of the left shoulder function (P < 0.01). Better preservation of the pulmonary function was also found in the 3D group as the decline of the OI post operation was significantly lower than that of the 2D group (P < 0.01). Changes of postoperative inflammatory markers, including procalcitonin [postoperative days (PODs) 4 and 7: P < 0.01], peripheral granulocytes (PODs 1, 4 and 7: P < 0.01) and hypersensitive C-reactive protein (POD 4: P < 0.01) in 3D-VATE patients were less than those in the 2D group. Moreover, utilization of the 3D technique extended the dissection of the thoracic lymph nodes (P < 0.01), with better exposure of nodes in the left recurrent laryngeal nerve (P = 0.031). CONCLUSION: 3D-VATE could be a more viable technique over 2D-VATE in terms of short-term outcomes for patients with esophageal cancer.