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The recognition, repetition and prediction of the post-failure motion process of long-runout landslides are key scientific problems in the prevention and mitigation of geological disasters. In this study, a new numerical method involving LPF3D based on a multialgorithm and multiconstitutive model was proposed to simulate long-runout landslides with high precision and efficiency. The following results were obtained: (a) The motion process of landslides showed a steric effect with mobility, including gradual disintegration and spreading. The sliding mass can be divided into three states (dense, dilute and ultradilute) in the motion process, which can be solved by three dynamic regimes (friction, collision, and inertial); (b) Coupling simulation between the solid grain and liquid phases was achieved, focusing on drag force influences; (c) Different algorithms and constitutive models were employed in phase-state simulations. The volume fraction is an important indicator to distinguish different state types and solid‒liquid ratios. The flume experimental results were favorably validated against long-runout landslide case data; and (d) In this method, matched dynamic numerical modeling was developed to better capture the realistic motion process of long-runout landslides, and the advantages of continuum media and discrete media were combined to improve the computational accuracy and efficiency. This new method can reflect the realistic physical and mechanical processes in long-runout landslide motion and provide a suitable method for risk assessment and pre-failure prediction.

With the construction of the Three Gorges Reservoir dam, frequent reservoir landslide events have been recorded. In recent years, multi-row stabilizing piles (MRSPs) have been used to stabilize massive reservoir landslides in China. In this study, two centrifuge model tests were carried out to study the unreinforced and MRSP-reinforced slopes subjected to reservoir water level (RWL) operation, using the Taping landslide as a prototype. The results indicate that the RWL rising can provide lateral support within the submerged zone and then produce the inward seepage force, eventually strengthening the slope stability. However, a rapid RWL drawdown may induce outward seepage forces and a sudden debuttressing effect, consequently reducing the effective soil normal stress and triggering partial pre-failure within the RWL fluctuation zone. Furthermore, partial deformation and subsequent soil structure damage generate excess pore water pressures, ultimately leading to the overall failure of the reservoir landslide. This study also reveals that a rapid increase in the downslope driving force due to RWL drawdown significantly intensifies the lateral earth pressures exerted on the MRSPs. Conversely, the MRSPs possess a considerable reinforcement effect on the reservoir landslide, transforming the overall failure into a partial deformation and failure situated above and in front of the MRSPs. The mechanical transfer behavior observed in the MRSPs demonstrates a progressive alteration in relation to RWL fluctuations. As the RWL rises, the mechanical states among MRSPs exhibit a growing imbalance. The shear force transfer factor (i.e. the ratio of shear forces on pile of the nth row to that of the first row) increases significantly with the RWL drawdown. This indicates that the mechanical states among MRSPs tend toward an enhanced equilibrium. The insights gained from this study contribute to a more comprehensive understanding of the failure mechanisms of reservoir landslides and the mechanical behavior of MRSPs in reservoir banks.

Analysis of the genesis and evolution mechanism of High and Steep Dangerous Rocks (HSDRs) are crucial for enhancing the capability of geological disaster risk prevention and control in reservoir areas. This study focuses on the Longmen Dangerous Rock Zone (LDRZ) in the Three Gorges Reservoir Area (TGRA), China, and employs an integrated investigation system proposed. The genesis and evolution of the LDRZ can be attributed to the early influence of the Indosinian movement, Yanshan movement, and the Himalayan movement. The development of joint fissures in the Longmenxia Anticline led to the presence of stacked blocks in the steep cliffs, forming the early prototype of the LDRZ. The increased base pressure caused by natural rainfall affecting High and Steep Dangerous Rock Masses (HSDRMs) above the 175 m water level is recoverable, which reflects the situation of HSDRMs before the impoundment in the TGRA. The HSDRMs affected by the water in the TGRA are simultaneously influenced by natural rainfall and reservoir water level fluctuation. The reservoir water leads to the rock masses deterioration at the base, resulting in an irreversible increase in base pressure. With the annual cyclical rise and fall of the water level in the TGRA, forming the current LDRZ.

Long-runout rockslides at high altitude have caused lots of severe casualties and huge economic losses in the world, becoming a focus issue in researches on mitigation for large-scale geological disasters. This paper systematically reviews the research process of high-altitude and long-runout rockslides and believes that conventional research on “high velocity and long runout” is difficult to adapt to the requirements of complex geohazards prevention and mitigation in high and extra-high mountains. The methodology on high-altitude and long-runout rockslides has been proposed that includes in the initiation at the high-position, the dynamics of chain-style disasters with a long-runout traveling and the risk assessment and mitigation. Then, the disaster-prone geostructure characteristics and early identification techniques of the high-altitude initiation zone, the long-runout transferring mechanism and boundary layer effect of high-velocity debris avalanche, and risk assessment and mitigation issues have been explored. Through the study in the high mountain and extra-high mountains of the Qinghai-Tibet Plateau indicates that the potential flow transferring mechanism of debris avalanche in high-altitude rockslides, the boundary layer effect of turbulent fluid and the plowing bodies. It is proposed that energy dissipation and risk mitigation methods can be used by modifying the boundary layer bottom slope of high potential debris avalanche, to increase the generation of turbulent kinetic energy in the boundary layer, and the dead zone range in front of barrier piles. Three research directions have been discussed, including the initiating mechanism of disaster-prone geostructure, the dynamic process of high-altitude and long-runout disaster chains, and the theory and technology of risk prevention and mitigation.

AbstractThe Wenchuan earthquake triggered many landslides, which caused many casualties and led to considerable property losses. Due to the compositionality of the hypocenter mechanism of the Wenchuan earthquake, research on the effects of a composite hypocenter on the dynamic responses of landslides is urgently necessary. Using geological field investigations, a block discrete element method simulation, and related theoretical analysis, the dynamic formation mechanism and main controlling mechanical factors of the Tangjiashan landslide were revealed. The results demonstrated the following. Firstly, the dynamic responses of the slope involved progressive deformation, critical failure, disintegration, fragmentation, collision, climb, return, and accumulation. Secondly, when the earthquake lasted for approximately 23 s, the critical failure occurred, and the sliding mass near the shoulder reached a vertical acceleration of approximately 2.8 g at this time. Thirdly, the second and third subhypocenters contributed to the progressive deformation and critical failure, and vertical seismic forces were dominant contributions to these responses. Fourthly, the disintegration, fragmentation, collision, climb, return, and accumulation were mainly controlled by the self-gravity and local topography and were slightly influenced by subhypocenters. Based on these conclusions, the study of the dynamic formation mechanism of this type of landslide has increased the level of understanding.

On one hand, anti-slide shaft technology can overcome the problems of blocking the seepage and drainage path in the slope by traditional anti-slide piles. On the other hand, it can reduce the excavation quantities when the vertical drainage and anti slide structures are separately constructed. Besides, it can fully provide the hydration-heat dissipation surface to ensure the overall structure quality. It has been an important technology in modern landslide prevention engineering, and the novel one of geological disaster, hydrogeology and underground engineering in recent years. The anti-slide shaft technology involves hydrodynamic mechanics and solid mechanics, as well as hydrodynamic model, structural model, engineering geological model, etc. Besides, its promoted application is restricted by some problems, such as the lack of mature theoretical system, the relatively complex of this spatial structural combination, and the difficulty of the construction technology. Thus, it is necessary to carry out targeted current status summary research. Based on a large number of relevant documents, patents and practical engineering applications at home and abroad, we summarize the characteristics and classification of anti-slide shaft structure (anti-liquefaction pile, hollow anti-slide shaft, box anti-slide shaft, etc), and find that the anti-slide shaft structure are mostly pile-type or tie-type, forming a 3-D structure system with the combination characteristics of seepage, collection, drainage and anti-slide. This kind of seepage-collection-drainage structures usually include water permeable holes, radiant seepage holes and drainage pipes. The demonstration of typical application examples show that although the anti-slide shafts have the advantage of significant improvement on the stability, there is still a large optimization space from its extensive use and diversification. Thus, the current complex construction process, unclear mechanical properties and drainage characteristics, imperfect stability calculation theory, plane layout optimization method to be improved in anti-slide shaft technology are important scientific issues and research trend, which need to be paid attention in the future. The solutions of these scientific problems are not only beneficial to improving the mechanical and drainage theory, but also beneficial to improving the overall application level of anti-slide shaft technology.

A massive rock and ice avalanche occurred on the western slope of the Ronti Gad valley in the northern part of Chamoli, Indian Himalaya, on 7 February 7, 2021. The avalanche on the high mountain slope at an elevation of 5600 m above sea level triggered a long runout disaster chain, including rock mass avalanche, debris avalanche, and flood. The disaster chain had a horizontal travel distance of larger than 17,600 m and an elevation difference of 4300 m. In this study, the disaster characteristics and dynamic process were analyzed by multitemporal satellite imagery. The results show that the massive rock and ice avalanche was caused by four large expanding discontinuity planes. The disaster chain was divided into five zones by satellite images and field observation, including source zone, transition zone, dynamic entrainment zone, flow deposition zone, and flood zone. The entrainment effect and melting water were recognized as the main causes of the long-runout distance. Based on the seismic wave records and field videos, the time progress of the disaster was analyzed and the velocity of frontal debris at different stages was calculated. The total analyzed disaster duration was 1247 s, and the frontal debris velocity colliding with the second hydropower station was approximately 23 m/s. This study also carried out the numerical simulation of the disaster by rapid mass movement simulation (RAMMS). The numerical results reproduced the dynamic process of the debris avalanche, and the mechanism of long-runout avalanche was further verified by parametric study. Furthermore, this study discussed the potential causes of disaster and flood and the roles of satellite images and seismic networks in the monitoring and early-warning.

Long-runout rockslides at high altitude could cause disaster chain in river basins and destroy towns and major infrasturctures. This paper firstly explores the initiation mechanism of high-altitude and long-runout rockslides. Two types of sliding-prone geostructure models, i.e. the fault control type in orogenic belt and the fold control type in platform area, are proposed. Then, large-scale experimental apparatus and associated numerical simulations are conducted to understanding the chain-style dynamics of rockslide-debris avalanche-debris flow. The results reveal the fragmentation effects, the rheological behaviors and the boundary layer effect of long-runout avalanche-debris flow. The dynamic characteristics of quasi-static-transition-inertia state and solid-liquid coupling in rapid movement of rockslide-debris avalanche-debris flow are investigated. Finally, the risk mitigation strategy of the non-structure and structure for resilient energy dissipation are illustrated for initiation, transition and deposition zones. The structural prevention and mitigation methods have been successfully applied to the high-altitude and long-runout rockslides in Zhouqu and Maoxian of the Wenchuan earthquake zone, as well as the other major geohazards in Qinghai-Tibet Plateau and its adjacent areas.

Basalt fiber-reinforced polymer bars are lightweight composite materials with high strength, low density, and excellent corrosion resistance. The anchor system made from basalt fiber-reinforced polymer bars is worthy of being developed and expected to be used in rock anchoring projects. In this work, four different basalt fiber-reinforced polymer anchor systems were designed, the influences of different design parameters on the ultimate bearing capacity of the anchor system were investigated through tension tests, and the failure modes of different anchor systems were elucidated. The test results indicated that failure modes, such as the transverse fracture of these bars and debonding of the bonding medium, were widely present in the wedge-modified anchor system and the steel-pipe-protected anchor system. These two anchor systems performed poorly with the wedge anchorage, whereas the basalt fiber-reinforced polymer bars protected by seamless steel pipes burst under the tension imposed by a universal testing machine. The threaded steel-pipe-bonded anchor system and the steel strand–basalt fiber-reinforced polymer bar composite anchor system had maximum anchorage efficiency coefficients of 97.7% and 98.5%, respectively. The bars in the corresponding test groups all exhibited burst failure, indicating that these two anchoring structures achieved effective anchorage of the basalt fiber-reinforced polymer bars.

Chalonglongbaqu gully is located on the right bank of Parlung Zangbo. The steeply changing topography has bred a large number of high-level geological disasters, threatening the downstream linear engineering. Therefore, this paper uses multi-source and multi-phase high-resolution remote sensing data to establish remote sensing interpretation signs of high-level geological disasters, determines the types of high-level geological disasters in the study area, and elaborates their development characteristics. The results show that the main types of geological disasters in the study area include high-level ice avalanches, high-level avalanches, and high-level landslides. Among them, there are 3 high-level ice avalanches, all of which are located on a slope with an altitude of 5000 m above the south slope of the upper reaches of the valley, with an area of more than 15×104 m2. There are 19 high-level avalanches, which are mostly distributed in the middle reaches of the valley and high and steep bank slopes on both sides of the upper main ditch. The northern slope is more than the southern slope. There are two high-level landslides located in the upper reaches of the valley, and the landslide is dominated by moraines. Under the action of strong earthquakes or heavy rainfall, the above-mentioned high-level geological disasters are prone to instability and blockage of ditch. After blocking the ditch, it is easy to induce secondary disaster chains such as floods and mudslides, which will cause the risk of blocking the river downstream of Parlung Zangbo.

This article takes the Benduo high deformed body in the upper reaches of Yigong Zangbo as an example, combined with the methods of field ground survey, UAV integrated photographic survey, optical remote sensing dynamic investigation and numerical simulation prediction, the development characteristics and possibility of the Benduo high deformed body are analyzed. Predict and analyze the risk of forming a disaster chain. The results of the study are as follows: (1) The Benduo high-position deformable body is located in the fault, the rock mass is broken, the rock mass structural surface is developed, and the strength is low. At present, there are 12 small collapses and 64 cracks in the strong deformation of Benduo's high deformation body. (2) According to the interpretation results of InSAR, it is found that the Benduo high-position deformable body has two deformation areas. Among them, the BX1 deformation area is larger and the maximum deformation rate reaches 85 mm/a. Once it loses stability and slides, it has a higher risk of blocking the river. (3) Prediction and analysis of the risk of the deformed body after the instability shows that the Benduo high-level deformed body will block the Yigong Zangbu after the instability, the average thickness of the accumulation body is 90 m, and the backwater length of the dammed lake is 25 km. The backwater area formed by the blockage of the dam poses a higher threat to the downstream villages and towns after the failure of the upstream Zhongyu Village. (4) According to the risk characteristics of the dam body, the treatment plan for the excavation of the spillway tunnel is discussed.

On 7 Feb 2021, a high-location glacier-rock avalanche and dammed the river, and late caused outburst flooding disaster on the Rich Ganges River in northern Chamoli, India, that destroyed hydropower stations and bridge facilities more than 20 kilometers downstream, and claimed nearly 200 deaths. This paper uses multi-period high-resolution remote sensing images to compare and analyze the characteristics of the landslide source area and accumulation area before and after the high-location ice rock landslide disaster in the Ganges River Basin of Chamoli, India, and preliminarily discuss the movement process of the landslide. The results show that before 2013, the creep displacement of the avalanche landslide was small, and the cracks in the ice and snow cover on the surface were not obvious. From 2013 to 2017, the creep displacement of avalanche landslides increased significantly, and as many as 62 ice cracks of various sizes were visible in the ice and snow cover, with the longest being 513 m. Satellite images on February 5, 2021 showed that these ice cracks had been connected and penetrated, with a maximum width of 15 m, and they were unstable and damaged on February 7. According to the post-sliding remote sensing image, the collapsed landslide was cut from 4 sets of large structural surfaces in different directions, with an area of about 0.32 km2, an average thickness of about 70 m, and a volume of about 23×106 m3. The collapsed landslide body loses stability and disintegrates and moves down the valley with a debris flow at high speed. Due to terrain blocking, some debris particles accumulate in the rapid terrain change zone and form a barrier dam. After the barrier dam body breaks, a mountain torrent disaster is formed.

High-altitude and long-runout landslides, commonly forming chains of secondary disasters, frequently occur in the Yigong Zangbo Basin, which has a complex geologic background. Identifying the potential hazards posed by disaster chains plays a vital role in assessing geohazards. Analysis of the potential hazards related to a landslide that occurred on 9 April 2000, in Tibet, China, known as the Yigong landslide, is studied using remote sensing technology and numerical simulations. Due to the warming of the climate, more extreme dry–wet cycles, and frequent earthquakes, the Yigong landslide area became extremely fragile and more sensitive to perturbations. Based on multiphase optical remote sensing and InSAR (Interferometric Synthetic Aperture Radar) technology, risk monitoring and identification of the Yigong landslide was conducted. The results show that there are two displacement deformation areas. These areas have a maximum displacement deformation rate of 60 mm/year and a maximum accumulative displacement of 160 mm and are likely to reoccur. Additionally, the risks of deformation areas collapsing and blocking the river, which would likely form a disaster chain, were analyzed by prediction simulation based on the numerical back-analysis associated with the 2000 Yigong landslide. The results show that if only one displacement deformation area collapses, the maximum accumulation height would reach 76 m; if the displacement deformation areas both collapse, the maximum accumulation height would reach 106 m. Both conditions would set off disaster chains resulting in river blockages and subsequent flood disasters. Therefore, this work demonstrates that prediction analysis based on remote sensing technology and numerical simulations are effective methods for identifying potential geohazards.

The susceptibility to gentamicin of N. gonorrhoeae isolates collected in three Chinese provinces and the correlation among the MICs of gentamicin, azithromycin, and ceftriaxone were investigated in this study. The effects of combinations from those three antibiotics were also in the scope of this study to determine the efficacy of gentamicin as a combination therapeutic drug. The agar dilution method was used to measure the minimum inhibitory concentrations (MICs) of ceftriaxone, azithromycin and gentamicin on N. gonorrhoeae isolates. The synergy between these three antimicrobials were determined using the agar dilution checkerboard method. Subgroup studies were conducted to explore differences between azithromycin- and ceftriaxone-sensitive and resistant isolates. A total of 139 (36.60%) and 233 (61.30%) isolates demonstrated full susceptibility and intermediate susceptibility to gentamicin, respectively. The correlation analysis showed that the MICs of ceftriaxone and azithromycin weakly correlated with the value of gentamicin. The overall results of the three antibiotic combinations revealed indifferent effects. Combination therapy established a significant reduction on the MIC value. Most of the N. gonorrhoeae isolates tested in this study demonstrated a certain degree of susceptibility to gentamicin. Overall, antimicrobial combinations of gentamicin with ceftriaxone or azithromycin demonstrate indifferent effects.

Previous studies regarding the prevalence of Autism Spectrum Disorder (ASD) in patients with Prader-Willi Syndrome (PWS) have implicated heterogenous findings. Additionally, the early screening of ASD high-risk population for ASD and identifying ASD risk factors in PWS patients have not been explored. This study included 218 Chinese PWS patients aged 3 months to 18 years old. 78% of subjects were identified as high risk for ASD by ASQ-3 Communication domain score for those younger than 3 years of age and 84% of subjects were classified as high risk for ASD by the GARS-3 for those aged 3 years and older. Among PWS clinical measurements, under-height (P = 0.0186), overweight (P = 0.0248), and obstructive sleep apnea (P = 0.0259) were each significantly correlated with ASD risk. These risk factors and their internal relationship with ASD or ASD traits warrant further studies.

Background: Neisseria gonorrhoeae (N. gonorrhoeae) is now recognized as a commonly reported sexually transmitted pathogen, and the increasing drug resistance of N. gonorrhoeae has become a serious public health problem. The accuracy of molecular detection for detecting moderate-level azithromycin resistance is not well-established. We summarized the data from studies of the N. gonorrhoeae 23S rRNA mutation at position 2611 with azithromycin resistance to determine the relationship between the mutation and resistance. Methods and Findings: In this systematic review and meta-analysis, two researchers independently searched six databases for studies with data for the azithromycin minimum inhibitory concentrations (MICs) and the 23S rRNA mutation C2611T of each N. gonorrhoeae isolate. Since the breakpoint of moderate-level resistance to azithromycin (ML-AzmR) was not determined, we divided the moderate level into two groups according to the range of MICs (moderate resistance limited to 2–128 mg/L or 4–128 mg/L) for data extraction. A random-effects model was used to calculate the pooled sensitivity rate, the specificity rate, the pooled positive likelihood ratio (PLR), the negative likelihood ratio (NLR), and the diagnostic odds ratio (DOR). Meta-regression analyses by detection method, isolates sampling (a random sample or not), location, and sample size were performed to explore the possible causes of heterogeneity. The potential publication bias of the included studies was conducted by the Deeks’ test. We included 20 studies in our study: 20 studies have data of N. gonorrhoeae with MICs between 2 and 128 mg/L with mutation or without mutation at position 2611(4759 samples), and 14 studies have data of N. gonorrhoeae with MICs between 4 and 128 mg/L (3367 samples). In the group with the moderate level of 2–128 mg/L, the pooled sensitivity rate of the molecular assays was determined to be 71.9% (95% CI, 67.6–74%), the pooled specificity rate was 98.7% (95% CI, 98.2–99.0%), and the DOR ranged from 55.0 to 351.3 (mean, 139.1). In the 4–128 mg/L group, the pooled sensitivity rate was 91.9% (95% CI, 88.9–94.2%), the pooled specificity rate was 95.9% (95% CI, 95.1–96.6%), and the DOR ranged from 41.9 to 364.1 (mean, 123.6). Conclusion: Through this meta-analysis, we found that the C2611T mutation of 23S rRNA is valuable for the molecular diagnostic of moderate-level azithromycin resistance (ML-AzmR) in N. gonorrhoeae, especially when the moderate level is set at 4–128 mg/L. This rapid molecular detection method can be used for the rapid identification of ML-AzmR isolates in the clinic.

The Three Gorges region in China was basically a geohazard-prone area prior to construction of the Three Gorges Reservoir (TGR). After construction of the TGR, the water level was raised from 70 m to 175 m above sea level (ASL), and annual reservoir regulation has caused a 30-m water level difference after impoundment of the TGR since September 2008. This paper first presents the spatiotemporal distribution of landslides in six periods of 175 m ASL trial impoundments from 2008 to 2014. The results show that the number of landslides sharply decreased from 273 at the initial stage to less than ten at the second stage of impoundment. Based on this, the reservoir-induced landslides in the TGR region can be roughly classified into five failure patterns, i.e. accumulation landslide, dip-slope landslide, reversed bedding landslide, rockfall, and karst breccia landslide. The accumulation landslides and dip-slope landslides account for more than 90%. Taking the Shuping accumulation landslide (a sliding mass volume of 20.7 × 106 m3) in Zigui County and the Outang dip-slope landslide (a sliding mass volume of about 90 × 106 m3) in Fengjie County as two typical cases, the mechanisms of reactivation of the two landslides are analyzed. The monitoring data and factor of safety (FOS) calculation show that the accumulation landslide is dominated by water level variation in the reservoir as most part of the mass body is under 175 m ASL, and the dip-slope landslide is controlled by the coupling effect of reservoir water level variation and precipitation as an extensive recharge area of rainfall from the rear and the front mass is below 175 m ASL. The characteristics of landslide-induced impulsive wave hazards after and before reservoir impoundment are studied, and the probability of occurrence of a landslide-induced impulsive wave hazard has increased in the reservoir region. Simulation results of the Ganjingzi landslide in Wushan County indicate the strong relationship between landslide-induced surge and water variation with high potential risk to shipping and residential areas. Regarding reservoir regulation in TGR when using a single index, i.e. 1-d water level variation, water resources are not well utilized, and there is also potential risk of disasters since 2008. In addition, various indices such as 1-d, 5-d, and 10-d water level variations are proposed for reservoir regulation. Finally, taking reservoir-induced landslides in June 2015 for example, the feasibility of the optimizing indices of water level variations is verified.

This paper presents findings from an investigation of the large-scale construction solid waste (CSW) landslide that occurred at a landfill at Shenzhen, Guangdong, China, on December 20, 2015, and which killed 77 people and destroyed 33 houses. The landslide involved 2.73×106 m3 of CSW and affected an area about 1100 m in length and 630 m in maximum width, making it the largest landfill landslide in the world. The investigation of this disaster used a combination of unmanned aerial vehicle surveillance and multistage remote-sensing images to reveal the increasing volume of waste in the landfill and the shifting shape of the landfill slope for nearly two years before the landslide took place, beginning with the creation of the CSW landfill in March, 2014, that resulted in the uncertain conditions of the landfill's boundaries and the unstable state of the hydrologic performance. As a result, applying conventional stability analysis methods used for natural landslides to this case would be difficult. In order to analyze this disaster, we took a multistage modeling technique to analyze the varied characteristics of the landfill slope's structure at various stages of CSW dumping and used the non-steady flow theory to explain the groundwater seepage problem. The investigation showed that the landfill could be divided into two units based on the moisture in the land: a front uint, consisted of the landfill slope, which had low water content; and a rear unit, consisted of fresh waste, which had a high water content. This structure caused two effects—surface-water infiltration and consolidation seepage that triggered the landslide in the landfill. Surface-water infiltration induced a gradual increase in pore water pressure head, or piezometric head, in the front slope because the infiltrating position rose as the volume of waste placement increased. Consolidation seepage led to higher excess pore water pressures as the loading of waste increased. We also investigated the post-failure soil dynamics parameters of the landslide deposit using cone penetration, triaxial, and ring-shear tests in order to simulate the characteristics of a flowing slide with a long run-out due to the liquefaction effect. Finally, we conclude the paper with lessons from the tens of catastrophic landslides of municipal solid waste around the world and discuss how to better manage the geotechnical risks of urbanization.

BackgroundIncreasing burden of STDs is one of China's major public health concerns. However, only a limited number of studies have ever investigated the prevalence of these STDs, particular for genital warts and its correlates among heterosexual males attending STD clinics in China. In order to fill this gap, we conducted a cross-sectional study among MSCs in Jiangmen, China, between the years of 2009 and 2010.MethodThe eligible participants were recruited from several STD-clinics in public hospitals. We collected demographic information and behaviors of the participants. After HIV and syphilis testing, we further checked whether the participants had genital warts and genital herpes. In addition, urine samples were collected from part of the participants for CT and NG testing.ResultsOf the 533 eligible participants, over three-fifths were aged 35 or below, nearly three quarters had no college degree, over three-fifths were residence of Jiangmen. The prevalence of HIV, syphilis, genital warts, genital herpes, CT and NG were 0.19%, 7.50%, 7.32%, 5.25%, 9.73% and 6.19%, respectively. Living with family members (versus living alone), no STD-related service in past year, experiencing STDs related symptoms in past year, and sex with FSWs in last three months were positively associated with genital warts, with adjusted ORs of 5.54 (95% CI 1.94-15.81), 2.26 (95% CI 1.08-4.74), 1.99 (95% CI 1.00-3.99) and 2.01 (95% CI 1.00-4.04), respectively.ConclusionOur study indicates that the prevalence of STDs among MSCs in Jiangmen was high, which may further spread HIV among MSCs. Targeted interventions that focused on STDs related services uptake should be implemented urgently.

BACKGROUND: Neisseria gonorrhoeae (NG) infection is a serious public health problem. The third-generation extended-spectrum cephalosporins (ESCs) have been used as the first-line treatment for NG infection for almost three decades. However, in recent years, treatment failures with the oral third-generation ESCs have been reported worldwide. This study aimed to estimate worldwide susceptibility rates of NG to cefixime and cefpodoxime by analyzing data from all relevant published studies. METHODOLOGY/PRINCIPAL FINDINGS: Two researchers independently searched five databases to identify studies on susceptibilities of NG to cefixime and cefpodoxime published between January 1, 1984 and October 15, 2012. A fixed-effect model was used to perform group analysis, and a χ2 test was employed to make subgroup comparison. Publication bias was assessed with the Begg rank correlation test. The pooled susceptibility rate of NG isolates to cefixime was 99.8% (95% CI: 99.7%-99.8%). The cefixime susceptibility rate of NG isolates from men was significantly lower than that from patients without information of gender or from men and women; the susceptibility rate of NG isolates from Asia was significantly lower than that from other continents; and the susceptibility rate of NG isolates collected before or during 2003 was significantly higher than that after 2003. The pooled susceptibility rate of NG isolates to cefpodoxime was 92.8% (95% CI: 89.0%-95.3%), which was lower than that to cefixime (92.8% vs. 99.8%, χ2 = 951.809, P

OBJECTIVES: To determine seropositivity of herpes simplex virus type 2 (HSV-2) infection and associated risk factors among female sex workers (FSWs) in Guangxi, China. METHODS: A convenience sample of FSWs was recruited from different types of sex work venues in two cities (Wuzhou and Hezhou) in Guangxi. Blood specimens were collected for ELISA-based detection of HSV-2 antibodies to examine the seropositivity of HSV-2 infection. Socio-demographic and behavioral data were collected through a structured questionnaire interview. Association of HSV-2 seropositivity with socio-demographic and behavioral characteristics and HIV status was analyzed. RESULTS: The overall prevalence of HSV-2 seropositivity among 2453 FSWs was 54.9% (95% confidence interval [CI], 52.9-56.9%). The HSV-2 seropositivity was independently associated with older age, low education level, non-Han minority, migration status, working in lower-tier venues and positive HIV status. CONCLUSIONS: The study indicates a high prevalence of HSV-2 infection among FSWs, particularly in those working in low-tier venues in study areas, suggesting the needs to further emphasize the inclusion of HSV-2 in surveillance and intervention programs in this population.