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Rainfall is a crucial issue affecting the entrance slope stability of mountain tunnels, as it decreases the shearing strength of soil and reduces the stability of tunnel entrance. This paper presents a case history of the collapse failure of a tunnel entrance in Yunnan Province under rainfall conditions, in which the failure mechanism and potential factors and treatment measures were discussed by field investigation, theoretical analysis, and in-situ monitoring. The analysis results show that the decrease of soil shear strength was mainly attributed to the decline of matric suction value of soil caused by the increase of soil water content. The decrease of the soil shear strength reduced the sliding resistance of the entrance slope and then triggered the collapse. Based on the results, three treatment measures to prevent a secondary tunnel entrance collapse due to rainfall are adopted, including anti-slide pile, grouting, and slope reinforcement. Combined with the field monitoring data, the effects of treatment measures were investigated. Lessons in this case study facilitate prevention and treatment of tunnel entrance constructions under rainfall conditions.

The mechanism underlying neurogenesis during embryonic spinal cord development involves a specific ligand/receptor interaction, which may be help guide neuroengineering to boost stem cell-based neural regeneration for the structural and functional repair of spinal cord injury. Herein, we hypothesized that supplying spinal cord defects with an exogenous neural network in the NT-3/fibroin-coated gelatin sponge (NF-GS) scaffold might improve tissue repair efficacy. To test this, we engineered tropomyosin receptor kinase C (TrkC)-modified neural stem cell (NSC)-derived neural network tissue with robust viability within an NF-GS scaffold. When NSCs were genetically modified to overexpress TrkC, the NT-3 receptor, a functional neuronal population dominated the neural network tissue. The pro-regenerative niche allowed the long-term survival and phenotypic maintenance of the donor neural network tissue for up to 8 weeks in the injured spinal cord. Additionally, host nerve fibers regenerated into the graft, making synaptic connections with the donor neurons. Accordingly, motor function recovery was significantly improved in rats with spinal cord injury (SCI) that received TrkC-modified NSC-derived neural network tissue transplantation. Together, the results suggested that transplantation of the neural network tissue formed in the 3D bioactive scaffold may represent a valuable approach to study and develop therapies for SCI., Graphical abstract Scheme 1. A neurotrophin-3 (NT-3) sustained-release bioscaffold supports the formation of tyrosine kinase receptor C (TrkC)-modified neural stem cell-derived neural network tissue with efficacy in repairing spinal cord injury.Image 1, Highlights • A NT-3 sustained-release scaffold confers a microenvironment partially simulating the developmental spinal cord. • The NT-3 microenvironment boosts neuronal differentiation of TrkC-modified NSCs by interactions between ligand and receptor. • TrkC-NSCs is self-organized into a neural network tissue with typical neural excitability in 3D bioactive scaffold in vitro. • The grafted neural network tissue can survive and maintain neural property, and improve motor function of paralyzed rats.

Recently, the use of nanomaterials (i.e., Nano-Silica (NS) and Nano-SiC(NC)) to improve the mechanical properties and durability performances of cement-based materials has received considerable attention. This work presents the effects of nanoparticles (NS), the specimen size, and the water-reducing agent on the antipullout strength between the reinforcement and cement mortar on the basis of the laboratory antipullout tests. The mechanism is, then, validated by the microscopic analysis with Scanning Electron Microscopy (SEM). Results show that NS can accelerate the hydration reaction of cement, produce more Calcium Silicate Hydrate (CSH) gel, and increase the density of the cement mortar, thereby improving the microstructure and antipullout strength. The moderate NS (1.0%) is recommended to improve antipullout between the reinforcement and cement mortar. Besides, the specimen size and water-reducing agent have an obvious influence on the antipullout strength. These results would provide guidance on the design or construction of the cement mortar with reinforcement.

To observe the clinical efficacy of DZWJY-1 type electronic moxibustion apparatus and traditional moxibustion in treating knee osteoarthritis (KOA). A total of 76 eligible patients were randomized into an electronic moxibustion apparatus group and a traditional moxibustion group, with 38 cases in each group. The electronic moxibustion apparatus group was intervened by DZWJY-1 type electronic moxibustion apparatus, and the traditional moxibustion group received moxa stick moxibustion for treatment. Neixiyan (EX-LE 4), Dubi (ST 35), Xuehai (SP 10) and Liangqiu (ST 34) were selected for both groups and the treatment was conducted 3 times a week for a total of 12 times. The visual analog scale (VAS) and the Western Ontario and McMaster Universities osteoarthritis index (WOMAC) scores were observed before treatment and after 6 and 12 sessions of treatment, respectively. There were 4 dropout cases in the traditional moxibustion group. Therefore, this trial had 72 valid cases, including 38 cases in the electronic moxibustion apparatus group and 34 cases in the traditional moxibustion group, the differences in the baseline data between the two groups were statistically insignificant (P>0.05). After 6 and 12 sessions of treatment, the VAS scores decreased significantly with the increase of treatment sessions in both groups (all P 0.05). The pain intensity was evaluated using the weighted value of VAS score. The markedly effective rate was 47.4% and the total effective rate was 89.5% in the electronic moxibustion apparatus group, versus 50.0% and 94.1% in the traditional moxibustion group, and the between-group differences were statistically insignificant (both P>0.05). After 6 and 12 sessions of treatment, the total score and the component scores including pain, stiffness and difficulty moving in the WOMAC decreased significantly with the increase of treatment sessions in both groups (all P 0.05). Electronic moxibustion apparatus and traditional moxibustion both are effective in reducing joint pain and improving joint function in KOA patients, and they are equivalent comparing the clinical efficacy.

To ensure the safety of shield tunneling near pile foundation and reduce the disturbance of this phenomenon in an urban metro in the loess area of China, a three-dimensional finite-element analysis model of shield-tunneling construction is established based on ABAQUS numerical simulation software and modified Cam-clay model. The deformation and ground settlement of adjacent-pile foundation during shield tunneling are analyzed. The law of descent is calculated and analyzed. Results show that the influence of tunnel shield on adjacent-pile foundation is primarily manifested in the X-direction displacement of the buried depth of the tunnel. During the shield-excavation process, the X-direction displacement of the pile increases gradually with decreased distance between the excavation face and the pile. When the distance between the pile axis and the excavation face of the tunnel is approximately[-0.5D, +0.5D], the displacement is the largest; when D continues to increase, the X-direction displacement is the largest. The displacement also continues to increase and eventually stabilizes. By obtaining the deformation curve of ground settlement, we find that the ground deformation is the largest above the tunnel axis and gradually decreases to both sides, whereas the pile cap is affected by uneven settlement. In the actual excavation of the tunnel project, strengthening the monitoring of the uneven settlement of the cap is necessary to take timely control measures.

X-ray computed tomography (CT), as an imaging technique, has played an important role in the area of material characterization in civil engineering during the past 40 years. It has promoted the investigation of materials from the macroscopic testing to the microscopic characterization. Though numerous researches have been done by using X-ray CT technique to investigate the microstructure, the mechanical behavior, and the durability of cement-based materials, there is no comprehensive review on the testing process and the results obtained. Based on the research progress in the past 40 years made on the cement-based materials, the relevant issues to the X-ray CT technique are reviewed in this study in terms of the equipment used, the sample preparation, the test methods, the data processing, and the results obtained. Particularly, this article focuses on assessing microstructure, mechanical behavior, damages from freeze-thaw cycles, carbonation, sulfate attack, alkali-silica reaction, and the quantification of permeability of cement-based materials by using X-ray CT. The results can serve as a guidance for future experimental design of the similar research and provide inspirations on improving equipment for broader applications to cement-based materials.

In this paper, a novel filtering method is designed for denoising remote sensing image. Firstly, the image domain of noisy image is partitioned into blocks for estimating the variance of Gaussian w...

Aims This study was aimed to investigate whether electroacupuncture (EA) would increase the secretion of neurotrophin‐3 (NT‐3) from injured spinal cord tissue, and, if so, whether the increased NT‐3 would promote the survival, differentiation, and migration of grafted tyrosine kinase C (TrkC)‐modified mesenchymal stem cell (MSC)‐derived neural network cells. We next sought to determine if the latter would integrate with the host spinal cord neural circuit to improve the neurological function of injured spinal cord. Methods After NT‐3‐modified Schwann cells (SCs) and TrkC‐modified MSCs were co‐cultured in a gelatin sponge scaffold for 14 days, the MSCs differentiated into neuron‐like cells that formed a MSC‐derived neural network (MN) implant. On this basis, we combined the MN implantation with EA in a rat model of spinal cord injury (SCI) and performed immunohistochemical staining, neural tracing, electrophysiology, and behavioral testing after 8 weeks. Results Electroacupuncture application enhanced the production of endogenous NT‐3 in damaged spinal cord tissues. The increase in local NT‐3 production promoted the survival, migration, and maintenance of the grafted MN, which expressed NT‐3 high‐affinity TrkC. The combination of MN implantation and EA application improved cortical motor‐evoked potential relay and facilitated the locomotor performance of the paralyzed hindlimb compared with those of controls. These results suggest that the MN was better integrated into the host spinal cord neural network after EA treatment compared with control treatment. Conclusions Electroacupuncture as an adjuvant therapy for TrkC‐modified MSC‐derived MN, acted by increasing the local production of NT‐3, which accelerated neural network reconstruction and restoration of spinal cord function following SCI., A schematic diagram showing that MSC‐derived neural network is better integrated with the host spinal cord neural network after the EA treatment.

To solve the imbalanced problem of wind pressure between left tunnel and right tunnel in the large-slopping tunnel, the complementary ventilation system is proposed, and the design theory and calcu...

This study simulates the total abatement cost (TAC) of CO2 emissions reduction for province, municipality, and autonomous district with different levels of gross domestic product (GDP) under the egalitarian allocation, sovereignty allocation, ability to pay, and polluter pays principles of an emissions trading policy to achieve five-year plans of 2020, 2025, and 2030 in China. The TACs are estimated by directional distance function, and savings of TAC are compared with and without the implementation of an emission trading policy nationwide. The TAC savings results for the group with low GDP per capita is consistent with that for the whole nation. Sacrificing economic development for provinces with high GDP and medium GDP is required to reach consensus for implementation of the trading policy. From province's standpoint, the sovereignty initial right allocation principle provides incentive for high-GDP-per-capita provinces to join the emissions trading mechanism for its consistency with the nation. Under such a circumstance, a subsidy policy is necessary along with the emissions trading mechanism to give less developed provinces incentives to join the emissions trading array.

This paper presents a review on the land subsidence caused by groundwater withdrawal in Xi’an, China. With the increasing demands of people’s livelihood and economy during the urbanization process, Xi’an has suffered severe hazards due to land subsidence caused by the excessive exploitation of groundwater since the 1960s. According to past records, the development of land subsidence in Xi’an can be divided into three stages; i) preliminary stage (1959 to 1971), ii) rapid development stage (1972 to 1990), and iii) slow development stage (1991 to present). In the 1990s, the annual groundwater withdrawal volume reached the maximum value of about 1388 × 106 m3/year, and the annual land subsidence also reached the maximum value (about 130 mm/year). The policy for controlling groundwater withdrawal was announced by the Xi’an Municipal Government in 1996, and then the land subsidence rate showed a significant descending tendency. Many researchers developed a series of approaches to yield the prediction of land subsidence caused by groundwater withdrawal, which can be divided into three categories: i) mathematical statistics approaches; ii) numerical approaches; iii) artificial intelligence approaches. Not only are the approaches’ advantages and disadvantages analyzed in this paper, but three emerging investigations on land subsidence in Xi’an are also discussed. The three emerging investigations aim to: i) analyze the relationship between land subsidence and ground fissures, ii) search the monitoring techniques available for obtaining more accurate data, and iii) investigate the effect of sand particle crushing under high stress level on the development of land subsidence.

Xi’an is the political, cultural and economic center in Northwestern China, and the demands for urbanization are growing dramatically in the past decades. During the rapid urbanization in Xi’an, ground fissure and land subsidence have been regarded as the two striking geohazards. At present, a total of fourteen ground fissures have been detected in Xi’an, among which eight ground fissures have a high level of activity, while the other six ground fissures are of lowly active. Several land subsidence funnels appear in different regions of Xi’an, and the annual land subsidence shows a decreasing tendency after 1991, which is estimated to be around 40 mm/year in recent years. The reasons triggering geohazards can be divided as: (1) natural factors and (2) anthropogenic factors. Analysis of the countermeasures against the prevention and mitigation of geohazards indicates that public awareness is an important issue to a success of the geoenvironment protection. In addition, the existing monitoring technologies (GPS, InSAR, and GIS) together with the technical improvement in other fields are deemed to be necessary for an effective monitoring and mitigation of the geohazards.

In the traditional tunneling method, the steel arch are often adopted to support surrounding rock to ensure the structural stability. If the steel arch is prestressed in time, tunnel support can effectively prevent the development of rock crack, thereby increasing the overall strength of tunnel support and suppress the deformation of the surrounding rock. Based on the mechanical model of steel arch established in this paper, the stress distribution of steel arch is investigated via the numerical simulation method, and the impact on surrounding rock is also analyzed. Through a field test, the rules of the arch strain distribution are observed and discussed. The results show that the prestressed steel arch structure can provide effective support and the stress gradually decreases from stress point to another arch springing. Furthermore, the stress distribution applied by the prestressed steel arch on the surrounding rock is uniform in a certain extent, and it is suggested that this construction method utilizing the prestressed steel arch to squeeze surrounding rock is feasible from a theoretical view.

When horizontal jet grouting is conducted in fine-grained soils, the injection of large volumes of fluid with high injection pressure into the ground may cause ground surface upheaval and the later...

Background To date, it has repeatedly been demonstrated that infusing bone marrow-derived stem cells (BMSCs) into acellular nerve scaffolds can promote and support axon regeneration through a peripheral nerve defect. However, harvesting BMSCs is an invasive and painful process fraught with a low cellular yield. Methods In pursuit of alternative stem cell sources, we isolated stem cells from the inguinal subcutaneous adipose tissue of adult Sprague–Dawley rats (adipose-derived stem cells, ADSCs). We used a co-culture system that allows isolated adult mesenchymal stem cells (MSCs) and Schwann cells (SCs) to grow in the same culture medium but without direct cellular contact. We verified SC phenotype in vitro by cell marker analysis and used red fluorescent protein-tagged ADSCs to detect their fate after being injected into a chemically extracted acellular nerve allograft (CEANA). To compare the regenerative effects of CEANA containing either BMSCs or ADSCs with an autograft and CEANA only on the sciatic nerve defect in vivo, we performed histological and functional assessments up to 16 weeks after grafting. Results In vitro, we observed reciprocal beneficial effects of ADSCs and SCs in the ADSC–SC co-culture system. Moreover, ADSCs were able to survive in CEANA for 5 days after in vitro implantation. Sixteen weeks after grafting, all results consistently showed that CEANA infused with BMSCs or ADSCs enhanced injured sciatic nerve repair compared to the acellular CEANA-only treatment. Furthermore, their beneficial effects on sciatic injury regeneration were comparable as histological and functional parameters evaluated showed no statistically significant differences. However, the autograft group was roundly superior to both the BMSC- or ADSC-loaded CEANA groups. Conclusion The results of the present study show that ADSCs are a viable alternative stem cell source for treating sciatic nerve injury in lieu of BMSCs.

Grouting has been deemed as one of the most effective measures for mitigation of ground movements during tunnel construction in soft soil. Notwithstanding that, a reliable measure to quantitatively evaluate the grouting-induced ground movements during shield tunnelling in soft soil has not yet been developed. This paper presents a simple method capable of quantitatively estimating the ground movements associated with grouting for tunnel-boring operations where the grouting parameters and soil properties are taken into consideration. The grouting process is simplified as the expansion of a cylindrical cavity with a uniform radial stress applied at soil-grout interface in a half plane, and the analytical solution proposed by Verruijt is introduced for determining the ground movements by the expansion of the cylindrical cavity. The proposed method is verified with a case history undertaken in London Clay. The results obtained suggest that this procedure would be helpful in managing the grouting parameters adopted in upcoming soft ground tunnelling project and mitigating the environmental impacts on nearby properties. Published version

Tissue engineering produces constructs with defined functions for the targeted treatment of damaged tissue. A complete spinal cord injury (SCI) model is generated in canines to test whether in vitro constructed neural network (NN) tissues can relay the excitatory signal across the lesion gap to the caudal spinal cord. Established protocols are used to construct neural stem cell (NSC)‐derived NN tissue characterized by a predominantly neuronal population with robust trans‐synaptic activities and myelination. The NN tissue is implanted into the gap immediately following complete transection SCI of canines at the T10 spinal cord segment. The data show significant motor recovery of paralyzed pelvic limbs, as evaluated by Olby scoring and cortical motor evoked potential (CMEP) detection. The NN tissue survives in the lesion area with neuronal phenotype maintenance, improves descending and ascending nerve fiber regeneration, and synaptic integration with host neural circuits that allow it to serve as a neuronal relay to transmit excitatory electrical signal across the injured area to the caudal spinal cord. These results suggest that tissue‐engineered NN grafts can relay the excitatory signal in the completely transected canine spinal cord, providing a promising strategy for SCI treatment in large animals, including humans., In vitro constructed engineered neural network tissue, characterized by a neuronal population with robust trans‐synaptic activities, can survive within the completely transected canine spinal cord, integrate with host neural circuits, and serve as a neuronal relay to transmit excitatory electrical signals across the injured area to the caudal spinal cord, leading to significant motor recovery within the paralyzed pelvic limbs.

According to the equivalent design theory, the length of a tunnel model can be shortened by applying a resistance grid in a tunnel ventilation model experiment. To study the effect of a resistance grid on the ventilation model, this paper analyses the influence of the distance, number, and type of resistance grids in ventilation experiments via a series of model experiments and takes the Dabieshan Tunnel as a case study for verification. The results show that the influence range of the resistance grid decreases with an increasing number of grid holes. When the number of holes per unit area of the grid is greater than 500, the influence length is less than three times the equivalent model diameter. The critical velocity of the model is almost unaffected by the grid spacing, grid number, or grid type. For the same model material, the resistance factor of the model decreases with increasing model size, and the local resistance factor of the grid in the model also proportionally decreases. When the aperture ratio is similar, the local resistance factor of a multiorifice plate grid is greater than that of a wire mesh grid, and the local resistance factor of a square hole grid is greater than that of a circular hole grid. With increasing aperture ratio, the decrease rate of the local resistance factor of a wire mesh grid is less than that of a multiorifice plate grid. The local resistance factor in each grid decreases with an increasing number of grid groups.

Frost damage to railway subgrade restricts the normal operation of railways and roadways in seasonally frozen areas. This paper proposes using stress release holes as a measure to alleviate frost heave force. Using a prediction model based on heat conduction and the seepage of unsaturated soil, a one-dimensional freezing experiment is conducted to calculate the frost heave of a soil column. Results suggest that stress release holes filled with mixed-materials can effectively alleviate frost heave and reduce vertical frost heave deformation from 36.8% to 65.3%. It is recommended that stress release holes be filled with a low stiffness, non-shrinking, cylindrical mixed-material which improves their waterproofing and strength enhancement. Furthermore, the burial depth of the stress release hole filling be kept above the height of supplementary water level, and that the filling's elastic modulus hold a value of 1/4 to 1/2 that of the surrounding soil.

To study the metabonomics for heat-clearing and detoxifying health function of Lonicera japonica in rats.Male Wistar rats were treated with decoction of Lonicera japonica through intragastric for 5 d. GC-MS was used to detect the changes in rats serum metabolites. Mass spectrometry analysis,PCA and other technologies were used to analyze the differences among their metabolites,and analyzed the endogenous product.There was a decline trend in citric acid cycle intermediates of Lonicera japonica treated group. On the contrary,amino acids and fatty acid intermediate product showed significant elevation,which revealed that the pathway of tricarboxylic acid cycle has been inhibited,and consistented with heat-clearing and detoxifying effect of Lonicera japonica.The metabonomics method by detecting the low-molecular-weight compounds can evaluate the heat-clearing and detoxifying health function of Lonicera japonica.

We have reported previously that bone marrow mesenchymal stem cell (MSC)-derived neural network scaffold not only survived in the injury/graft site of spinal cord but also served as a “neuronal relay” that was capable of improving the limb motor function in a complete spinal cord injury (SCI) rat model. It remained to be explored whether such a strategy was effective for repairing the large spinal cord tissue loss as well as restoring motor function in larger animals. We have therefore extended in this study to construct a canine MSC-derived neural network tissue in vitro with the aim to evaluate its efficacy in treating adult beagle dog subjected to a complete transection of the spinal cord. The results showed that after co-culturing with neurotropin-3 overexpressing Schwann cells in a gelatin sponge scaffold for 14 days, TrkC overexpressing MSCs differentiated into neuron-like cells. In the latter, some cells appeared to make contacts with each other through synapse-like structures with trans-synaptic electrical activities. Remarkably, the SCI canines receiving the transplantation of the MSC-derived neural network tissue demonstrated a gradual restoration of paralyzed limb motor function, along with improved electrophysiological presentation when compared with the control group. Magnetic resonance imaging and diffusion tensor imaging showed that the canines receiving the MSC-derived neural network tissue exhibited robust nerve tract regeneration in the injury/graft site. Histological analysis showed that some of the MSC-derived neuron-like cells had survived in the injury/graft site up to 6.5 months. Implantation of MSC-derived neural network tissue significantly improved the microenvironment of the injury/graft site. It is noteworthy that a variable number of them had integrated with the regenerating corticospinal tract nerve fibers and 5-HT nerve fibers through formation of synapse-like contacts. The results suggest that the transplanted MSC-derived neural network tissue may serve as a structural and functional “neuronal relay” to restore the paralyzed limb motor function in the canine with complete SCI.

Tumor markers are most popularly used in diagnosis of various cancers clinically. However, the confounding factors of individual background diversities, such as genetics, food preferences, living styles, physical exercises, etc., greatly challenge the identification of tumor markers. Study of the metabolic impact of inoculated tumors on model animals can facilitate the identification of metabolomic markers relevant to tumor insult. In this study, serum metabolites from nude mice (n = 14) inoculated with human H460 cells (human nonsmall cell lung carcinoma) were profiled using gas chromatography time-of-flight mass spectrometry. The mice with inoculated tumors showed an obviously different metabolic pattern from the control; identification of the discriminatory metabolites suggested the metabolic perturbation of free fatty acids, amino acids, glycolysis and tricarboxylic acid (TCA) cycle turnover. The significantly decreased TCA intermediates, free fatty acids, 3-hydroxybutyric acid and fluctuating amino acids (t-test, p < 0.05) in serum of tumor-bearing mice characterized the metabolic impact of local inoculated H460 tumor cells on the whole system. This indicates that they are candidate metabolomic markers for translational study of lung cancer, clinically. Copyright © 2015 John Wiley & Sons, Ltd.

The problem of optimal sensor placement plays a key role in the success of structural health monitoring (SHM) systems. In this study, a new method is presented to investigate the optimization problem of sensor placement on gantry crane structures. The method is a combination of an improved harmony search (HS) algorithm and the modal assurance criterion (MAC). Firstly, we review previous studies on setting reasonable values for HS parameters that have the most impact on the result, and highlight the lack of general rules governing this aspect. Based on more efficient HS algorithms resulting from those studies, we apply our proposed technique to the optimization problem of sensor placement on gantry crane structures. The purpose of the optimization method is to select the optimal sensor locations on gantry crane girders to establish a sensor network for an SHM system. Our results show that the HS algorithm is a powerful search and optimization technique that can lead to a better solution to the problem of engineering optimization. The mode of a crane structure could be identified more easily when different mode shape orientations are considered comprehensively.

The interfacial compatibility between compact TiO 2 and perovskite layers is critical for the performance of planar heterojunction perovskite solar cells (PSCs). A compact TiO 2 film employed as an electron-transport layer (ETL) was modified using 3-aminopropyl trimethoxy silane (APMS) hydrolysate. The power conversion efficiency (PCE) of PSCs composed of an APMS-hydrolysate-modified TiO 2 layer increased from 13.45 to 15.79%, which was associated with a significant enhancement in the fill factor (FF) from 62.23 to 68.04%. The results indicate that APMS hydrolysate can enhance the wettability of γ-butyrolactone (GBL) on the TiO 2 surface, form a perfect CH 3 NH 3 PbI 3 film, and increase the recombination resistance at the interface. This work demonstrates a simple but efficient method to improve the TiO 2 /perovskite interface that can be greatly beneficial for developing high-performance PSCs.

Frost heave can be substantially reduced if frost deformation of seasonally frozen ground is allowed to occur to a certain extent in the lateral direction. This controlled process can be achieved with a new approach of using stress release holes (SRHs) to decrease the frost heave. Experiments were designed and conducted based on one-dimensional frozen soil samples in closed or open systems. After being frozen for 48 h or 72 h, the soil samples with and without SRHs were then compared for their differences in frost heave deformation, temperature, frost heave rate, and moisture migration. The effects of soil samples with different Hole Ratio in Area (HRA), SRHs, and SRH filling materials are also studied. Results show that when the compaction coefficient Kcc decreases, there is resulting increase in frost heave. Furthermore, with an increasing ratio of HRA, the deformation and the frost heave rate decreases. The maximum frost heave of saturated soil samples with filled SRHs can be effectively decreased in both open and closed systems. Consequently, SRHs with filling are an appealing treatment measure that can be taken to decrease the frost heave of seasonally frozen soils.

Based on newly collected materials from the Lower Triassic Feixianguan Formation of Xiongwu section in Xingyi, Guizhou and the Ximatang Formation of Ximatang section in Qiubei, Yunnan, southern China, nine species belonging to seven genera are described. Two bivalve assemblages are recognized and regionally correlated in South China. The bivalve assemblage from the Feixianguan Formation of Xiongwu exhibits a higher diversity including seven species belonging to seven genera: Claraia griesbachi , Leptochondria virgalensis , Entolium ( Entolium ) microtis , Towapteria scythicum , Bakevillia exporrecta , Bositra sp., and Unionites ? fassaensis . In contrast, the bivalve assemblage from the Ximatang Formation of Ximatang has a much lower diversity, consisting of only two species, i.e., Claraia griesbachi and Claraia radialis . Additionally, C. griesbachi and C. radialis , as the most common species of Claraia in the Early Triassic, are revised.

Globally, the Jurassic cemented ostreid bivalves from northern Tibet, SW China, have a pan-tropical distribution pattern between palaeolatitudes of 60° South and North. Ostreid bivalves have tiny to large larvae, and nearly all of them have a cemented mode of life during their adult stage. The distribution pattern and the habits of the Jurassic ostreid bivalves revealed that, in the Jurassic time interval, all seas and oceans were interconnected, and ostreid bivalves were very capable of dispersion through their planktonic larval stage or as pseudoplankton during the post-larval stage, and even were able to cross the palaeo-Pacific Ocean from east to west. However, latitudinal temperature variation limited the distribution of these thermophilous bivalves to the lower and middle latitudes.